ORGO

SEC source: 0001661181-19-000008 · edgar.xml · nonDerivative · entry 1

KATZ MICHAEL W · CIK 0001279930 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,000

F1 · price: The price reported in Column 4 is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $4.495 to $4.50, inclusive. The reporting person undertakes to provide to Organogenesis Holdings Inc. ("ORGO"), any security holder of ORGO, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote (1) to this Form 4.

SEC source: 0001661181-19-000006 · edgar.xml · nonDerivative · entry 3

NUSSDORF GLENN H · CIK 0001244191 · Director · 10% owner

Wisdom Starr · CIK 0001760694 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,946,823

F1 · shares: The reported securities were purchased and are held directly by Glenn H. Nussdorf, who is a member of the Group (as defined below).

F4 · price: The price reported in Column 4 is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $4.37 to $4.92, inclusive. The reporting person undertakes to provide to ORGO, any security holder of ORGO, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote (4) to this Form 4.

SEC source: 0001661181-19-000010 · edgar.xml · nonDerivative · entry 2

MACKIE WAYNE D · CIK 0001240034 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 82,000

F2 · price: The price reported in Column 4 is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $4.31 to $4.85, inclusive. The reporting person undertakes to provide to ORGO, any security holder of ORGO, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote (2) to this Form 4.

SEC source: 0001661181-19-000005 · edgar.xml · nonDerivative · entry 2

Ades Alan A. · CIK 0001757286 · Director · 10% owner

ERANI ALBERT · CIK 0001074084 · Director · 10% owner

Erani Dennis · CIK 0001760685 · 10% owner

Organo PFG LLC · CIK 0001757580 · 10% owner

Organo Investors LLC · CIK 0001757573 · 10% owner

Alan Ades 2014 GRAT · CIK 0001757567 · 10% owner

Albert Erani Family Trust dated 12/29/2012 · CIK 0001760663 · 10% owner

Dennis Erani 2012 Issue Trust dated 12/20/12 · CIK 0001757455 · 10% owner

GN 2016 Organo 10-Year GRAT u/a/d September 30, 2016 · CIK 0001757452 · 10% owner

GN 2016 Family Trust u/a/d August 12, 2016 · CIK 0001757453 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,896,823

F3 · shares: The reported securities were purchased and are held directly by Dennis Erani, who is a member of the Group.

SEC source: 0001661181-19-000005 · edgar.xml · nonDerivative · entry 1

Ades Alan A. · CIK 0001757286 · Director · 10% owner

ERANI ALBERT · CIK 0001074084 · Director · 10% owner

Erani Dennis · CIK 0001760685 · 10% owner

Organo PFG LLC · CIK 0001757580 · 10% owner

Organo Investors LLC · CIK 0001757573 · 10% owner

Alan Ades 2014 GRAT · CIK 0001757567 · 10% owner

Albert Erani Family Trust dated 12/29/2012 · CIK 0001760663 · 10% owner

Dennis Erani 2012 Issue Trust dated 12/20/12 · CIK 0001757455 · 10% owner

GN 2016 Organo 10-Year GRAT u/a/d September 30, 2016 · CIK 0001757452 · 10% owner

GN 2016 Family Trust u/a/d August 12, 2016 · CIK 0001757453 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,896,723

F1 · shares: The reported securities were purchased and are held directly by Glenn H. Nussdorf, who is a member of the Group (as defined below).

F2 · price: The price reported in Column 4 is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $4.28 to $4.48, inclusive. The reporting person undertakes to provide to Organogenesis Holdings Inc. ("ORGO"), any security holder of ORGO, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote (2) to this Form 4.

SEC source: 0001140361-19-016217 · form4.xml · nonDerivative · entry 1

Avista Capital Managing Member IV, LLC · CIK 0001761175 · Director · 10% owner

Avista Acquisition Corp. · CIK 0001661187 · Director · 10% owner

Avista Acquisition, LLC · CIK 0001686388 · Director · 10% owner

Avista Capital Partners IV, L.P. · CIK 0001664176 · Director · 10% owner

Avista Capital Partners (Offshore) IV, L.P. · CIK 0001664173 · Director · 10% owner

Avista Capital Partners IV GP, L.P. · CIK 0001761195 · Director · 10% owner

Dean Thompson · CIK 0001069096 · Director · 10% owner

Burgstahler David F · CIK 0001374179 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 17,199,665

F2 · shares: The number of securities reported represents an aggregate number of shares of Class A common stock of the Issuer ("Common Stock") purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. Each Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares of Common Stock purchased by the Reporting Person at each separate price within the range.

F3 · shares: Represents an aggregate of 100,269 shares of Common Stock purchased by ACP Onshore and 99,731 shares of Common Stock purchased by ACP Offshore.

F2 · price: The number of securities reported represents an aggregate number of shares of Class A common stock of the Issuer ("Common Stock") purchased in multiple market transactions over a range of purchase prices. The price reported represents the weighted average price per share. Each Reporting Person undertakes to provide the staff of the SEC, the Issuer, or a stockholder of the Issuer, upon request, the number of shares of Common Stock purchased by the Reporting Person at each separate price within the range.

F4 · price: Purchase prices range from $4.44 to $4.75 per share, inclusive.

F5 · balance_after: Represents 8,097,194 shares of Common Stock owned directly by ACP Onshore, 8,053,780 shares of Common Stock owned directly by ACP Offshore, and 1,048,691 shares of Common Stock owned directly by the Sponsor.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: Avista Acquisition Corp. (the "Sponsor"); Avista Acquisition LLC, which is the sole shareholder of the Sponsor; Avista Capital Partners IV, L.P. ("ACP Onshore"); Avista Capital Partners (Offshore) IV, L.P. ("ACP Offshore"); Avista Capital Partners IV GP, L.P. ("Avista GP"), which is the general partner of ACP Onshore and ACP Offshore; Avista Capital Managing Member IV, LLC, which is the general partner of Avista GP; Thompson Dean; and David Burgstahler.

F12 · ownership.nature: Because of the relationship among the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. Joshua Tamaroff, an employee of an affiliate of the Reporting Persons, serves on the board of directors of the Issuer as a representative of the Reporting Persons.

F13 · ownership.nature: Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001661181-19-000012 · edgar.xml · nonDerivative · entry 1

Leibowitz Arthur S · CIK 0001467329 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,000

SEC source: 0001661181-19-000006 · edgar.xml · nonDerivative · entry 2

NUSSDORF GLENN H · CIK 0001244191 · Director · 10% owner

Wisdom Starr · CIK 0001760694 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,896,823

F3 · shares: The reported securities were purchased and are held directly by Dennis Erani, who is a member of the Group.

SEC source: 0001661181-19-000006 · edgar.xml · nonDerivative · entry 1

NUSSDORF GLENN H · CIK 0001244191 · Director · 10% owner

Wisdom Starr · CIK 0001760694 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,896,723

F1 · shares: The reported securities were purchased and are held directly by Glenn H. Nussdorf, who is a member of the Group (as defined below).

F2 · price: The price reported in Column 4 is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $4.28 to $4.48, inclusive. The reporting person undertakes to provide to Organogenesis Holdings Inc. ("ORGO"), any security holder of ORGO, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote (2) to this Form 4.

SEC source: 0001661181-19-000010 · edgar.xml · nonDerivative · entry 1

MACKIE WAYNE D · CIK 0001240034 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 50,000

F1 · price: The price reported in Column 4 is a weighted-average price. These shares were purchased in multiple transactions at prices ranging from $4.15 to $4.48, inclusive. The reporting person undertakes to provide to Organogenesis Holdings Inc. ("ORGO"), any security holder of ORGO, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote (1) to this Form 4.

SEC source: 0001140361-19-015434 · form4.xml · derivative · entry 2

Avista Capital Managing Member IV, LLC · CIK 0001761175 · Director · 10% owner

Avista Acquisition Corp. · CIK 0001661187 · Director · 10% owner

Avista Acquisition, LLC · CIK 0001686388 · Director · 10% owner

Avista Capital Partners IV, L.P. · CIK 0001664176 · Director · 10% owner

Avista Capital Partners (Offshore) IV, L.P. · CIK 0001664173 · Director · 10% owner

Avista Capital Partners IV GP, L.P. · CIK 0001761195 · Director · 10% owner

Dean Thompson · CIK 0001069096 · Director · 10% owner

Burgstahler David F · CIK 0001374179 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 0

Underlying: Class A common stock · 2,050,000 shares

Expires 2023-12-10

F5 · derivative.exercise_price: Each warrant entitled the holder to purchase from the Issuer shares of Common Stock at a price of $5.75 per-half share of Common Stock (or $11.50 per whole share), subject to adjustments.

F2 · kind: Based on a ratio of 0.095 shares per warrant, ACP Onshore and ACP Offshore exchanged (with the Issuer) 2,055,510 warrants and 2,044,490 warrants, respectively, for 195,274 shares and 194,227 shares, respectively (the "Warrant Exchange").

F2 · price: Based on a ratio of 0.095 shares per warrant, ACP Onshore and ACP Offshore exchanged (with the Issuer) 2,055,510 warrants and 2,044,490 warrants, respectively, for 195,274 shares and 194,227 shares, respectively (the "Warrant Exchange").

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: Avista Acquisition Corp. (the "Sponsor"); Avista Acquisition LLC, which is the sole shareholder of the Sponsor; Avista Capital Partners IV, L.P. ("ACP Onshore"); Avista Capital Partners (Offshore) IV, L.P. ("ACP Offshore"); Avista Capital Partners IV GP, L.P. ("Avista GP"), which is the general partner of ACP Onshore and ACP Offshore; Avista Capital Managing Member IV, LLC, which is the general partner of Avista GP; Thomspon Dean; and David Burgstahler.

F6 · ownership.nature: Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001140361-19-015434 · form4.xml · nonDerivative · entry 1

Avista Capital Managing Member IV, LLC · CIK 0001761175 · Director · 10% owner

Avista Acquisition Corp. · CIK 0001661187 · Director · 10% owner

Avista Acquisition, LLC · CIK 0001686388 · Director · 10% owner

Avista Capital Partners IV, L.P. · CIK 0001664176 · Director · 10% owner

Avista Capital Partners (Offshore) IV, L.P. · CIK 0001664173 · Director · 10% owner

Avista Capital Partners IV GP, L.P. · CIK 0001761195 · Director · 10% owner

Dean Thompson · CIK 0001069096 · Director · 10% owner

Burgstahler David F · CIK 0001374179 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 16,999,665

F2 · kind: Based on a ratio of 0.095 shares per warrant, ACP Onshore and ACP Offshore exchanged (with the Issuer) 2,055,510 warrants and 2,044,490 warrants, respectively, for 195,274 shares and 194,227 shares, respectively (the "Warrant Exchange").

F2 · price: Based on a ratio of 0.095 shares per warrant, ACP Onshore and ACP Offshore exchanged (with the Issuer) 2,055,510 warrants and 2,044,490 warrants, respectively, for 195,274 shares and 194,227 shares, respectively (the "Warrant Exchange").

F3 · balance_after: Represents 7,996,925 shares of Common Stock owned directly by ACP Onshore and 7,954,049 shares of Common Stock owned directly by ACP Offshore, in each case, following the Warrant Exchange, and 1,048,691 shares of Common Stock owned directly by the Sponsor.

F4 · balance_after: Because of the relationship among the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests.Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. Joshua Tamaroff, an employee of an affiliate of the Reporting Persons, serves on the board of directors of the Issuer as a representative of the Reporting Persons.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: Avista Acquisition Corp. (the "Sponsor"); Avista Acquisition LLC, which is the sole shareholder of the Sponsor; Avista Capital Partners IV, L.P. ("ACP Onshore"); Avista Capital Partners (Offshore) IV, L.P. ("ACP Offshore"); Avista Capital Partners IV GP, L.P. ("Avista GP"), which is the general partner of ACP Onshore and ACP Offshore; Avista Capital Managing Member IV, LLC, which is the general partner of Avista GP; Thomspon Dean; and David Burgstahler.

F6 · ownership.nature: Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001661181-19-000002 · edgar.xml · derivative · entry 1

KATZ MICHAEL W · CIK 0001279930 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Common Stock · 100,000 shares

Expires 2029-05-22

F1 · derivative.exercise_date: The shares underlying the option shall vest 20% annually beginning on May 22, 2020 and will be fully vested on May 22, 2024.

SEC source: 0001661181-18-000047 · edgar.xml · nonDerivative · entry 3

Ades Alan A. · CIK 0001757286 · Director · 10% owner

ERANI ALBERT · CIK 0001074084 · Director · 10% owner

Erani Dennis · CIK 0001760685 · 10% owner

Organo PFG LLC · CIK 0001757580 · 10% owner

Organo Investors LLC · CIK 0001757573 · 10% owner

Alan Ades 2014 GRAT · CIK 0001757567 · 10% owner

Albert Erani Family Trust dated 12/29/2012 · CIK 0001760663 · 10% owner

Dennis Erani 2012 Issue Trust dated 12/20/12 · CIK 0001757455 · 10% owner

GN 2016 Organo 10-Year GRAT u/a/d September 30, 2016 · CIK 0001757452 · 10% owner

GN 2016 Family Trust u/a/d August 12, 2016 · CIK 0001757453 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,846,723

F5 · price: Received by Glenn H. Nussdorf in connection with the Merger in exchange for 90,069 shares of common stock of Organogenesis previously held by Mr. Nussdorf.

F6 · ownership.direct: The reported securities are held directly by Glenn H. Nussdorf, who is a member of the Group.

SEC source: 0001661181-18-000047 · edgar.xml · nonDerivative · entry 2

Ades Alan A. · CIK 0001757286 · Director · 10% owner

ERANI ALBERT · CIK 0001074084 · Director · 10% owner

Erani Dennis · CIK 0001760685 · 10% owner

Organo PFG LLC · CIK 0001757580 · 10% owner

Organo Investors LLC · CIK 0001757573 · 10% owner

Alan Ades 2014 GRAT · CIK 0001757567 · 10% owner

Albert Erani Family Trust dated 12/29/2012 · CIK 0001760663 · 10% owner

Dennis Erani 2012 Issue Trust dated 12/20/12 · CIK 0001757455 · 10% owner

GN 2016 Organo 10-Year GRAT u/a/d September 30, 2016 · CIK 0001757452 · 10% owner

GN 2016 Family Trust u/a/d August 12, 2016 · CIK 0001757453 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,663,882

F3 · price: Received by Albert Erani in connection with the Merger in exchange for 385,174 shares of common stock of Organogenesis previously held by Mr. Erani.

F4 · ownership.direct: The reported securities are held directly by Albert Erani, who is a member of the Group.

SEC source: 0001661181-18-000047 · edgar.xml · nonDerivative · entry 1

Ades Alan A. · CIK 0001757286 · Director · 10% owner

ERANI ALBERT · CIK 0001074084 · Director · 10% owner

Erani Dennis · CIK 0001760685 · 10% owner

Organo PFG LLC · CIK 0001757580 · 10% owner

Organo Investors LLC · CIK 0001757573 · 10% owner

Alan Ades 2014 GRAT · CIK 0001757567 · 10% owner

Albert Erani Family Trust dated 12/29/2012 · CIK 0001760663 · 10% owner

Dennis Erani 2012 Issue Trust dated 12/20/12 · CIK 0001757455 · 10% owner

GN 2016 Organo 10-Year GRAT u/a/d September 30, 2016 · CIK 0001757452 · 10% owner

GN 2016 Family Trust u/a/d August 12, 2016 · CIK 0001757453 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 66,881,978

F1 · price: Received by Alan A. Ades in connection with the Issuer's business combination (the "Merger") with Organogenesis Inc. ("Organogenesis") in accordance with the terms of the Agreement and Plan of Merger dated as of August 17, 2018 among the Issuer, which was then referred to as Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis, in exchange for 3,093,320 shares of common stock of Organogenesis previously held by Mr. Ades.

F2 · ownership.direct: The reported securities are held directly by Alan A. Ades, who is a member of the Group (as defined below).

SEC source: 0001140361-18-045047 · form4.xml · derivative · entry 4

Burgstahler David F · CIK 0001374179 · Director · President & CEO · 10% owner

Dean Thompson · CIK 0001069096 · Director · Executive Chairman · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 4,100,000

Underlying: Class A Common Stock · 2,050,000 shares

Expires 2023-12-10

F7 · derivative.exercise_price: Each warrant entitles the holder to purchase from the Issuer the number of shares of Class A common stock at the price of $5.75 per half-share (or $11.50 per whole share), subject to adjustments.

F2 · kind: The Reporting Persons acquired indirectly in a private placement from Avista Healthcare Public Acquisition Corp. (prior to the Issuer's Business Combination) an aggregate of 9,022,741 shares of Class A common stock, including 4,523,497 shares owned through Fund IV and 4,499,244 shares owned through Offshore Fund IV, and an aggregate of 4,100,000 warrants to purchase shares of Class A common stock, including 2,055,510 warrants to purchase 1,027,755 shares through Fund IV and 2,044,490 warrants to purchase 1,022,245 shares owned through Offshore Fund IV warrants to purchase one-half of one share of Class A common stock for an aggregate purchase price of $46,000,000.

F2 · shares: The Reporting Persons acquired indirectly in a private placement from Avista Healthcare Public Acquisition Corp. (prior to the Issuer's Business Combination) an aggregate of 9,022,741 shares of Class A common stock, including 4,523,497 shares owned through Fund IV and 4,499,244 shares owned through Offshore Fund IV, and an aggregate of 4,100,000 warrants to purchase shares of Class A common stock, including 2,055,510 warrants to purchase 1,027,755 shares through Fund IV and 2,044,490 warrants to purchase 1,022,245 shares owned through Offshore Fund IV warrants to purchase one-half of one share of Class A common stock for an aggregate purchase price of $46,000,000.

F2 · price: The Reporting Persons acquired indirectly in a private placement from Avista Healthcare Public Acquisition Corp. (prior to the Issuer's Business Combination) an aggregate of 9,022,741 shares of Class A common stock, including 4,523,497 shares owned through Fund IV and 4,499,244 shares owned through Offshore Fund IV, and an aggregate of 4,100,000 warrants to purchase shares of Class A common stock, including 2,055,510 warrants to purchase 1,027,755 shares through Fund IV and 2,044,490 warrants to purchase 1,022,245 shares owned through Offshore Fund IV warrants to purchase one-half of one share of Class A common stock for an aggregate purchase price of $46,000,000.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: David Burgstahler and Thompson Dean. Messrs. Burgstahler and Dean are managers of Avista Acquisition LLC, the sole shareholder of Avista Acquisition Corp. (the "Sponsor"), and are members of the investment committee of Avista Capital Partners IV GP, L.P., the general partner of Avista Capital Partners IV, L.P. ("Fund IV") and Avista Capital Partners (Offshore) IV, L.P. ("Offshore Fund IV"), and each has veto rights over the voting and disposition of the securities of the Issuer.

F8 · ownership.nature: Because of the relationship between the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001140361-18-045047 · form4.xml · derivative · entry 3

Burgstahler David F · CIK 0001374179 · Director · President & CEO · 10% owner

Dean Thompson · CIK 0001069096 · Director · Executive Chairman · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 1,048,691

Underlying: Class A Ordinary Shares · 3,247,668 shares

Expires not disclosed

F5 · derivative.exercise_price: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of the Issuer, the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F6 · kind: The 3,247,668 Class B Shares were indirectly forfeited by the Reporting Persons to the Issuer through Sponsor for no consideration prior to the closing of the Business Combination.

F6 · shares: The 3,247,668 Class B Shares were indirectly forfeited by the Reporting Persons to the Issuer through Sponsor for no consideration prior to the closing of the Business Combination.

F6 · price: The 3,247,668 Class B Shares were indirectly forfeited by the Reporting Persons to the Issuer through Sponsor for no consideration prior to the closing of the Business Combination.

F5 · derivative.exercise_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of the Issuer, the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F5 · derivative.expiration_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of the Issuer, the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: David Burgstahler and Thompson Dean. Messrs. Burgstahler and Dean are managers of Avista Acquisition LLC, the sole shareholder of Avista Acquisition Corp. (the "Sponsor"), and are members of the investment committee of Avista Capital Partners IV GP, L.P., the general partner of Avista Capital Partners IV, L.P. ("Fund IV") and Avista Capital Partners (Offshore) IV, L.P. ("Offshore Fund IV"), and each has veto rights over the voting and disposition of the securities of the Issuer.

F8 · ownership.nature: Because of the relationship between the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001140361-18-045047 · form4.xml · nonDerivative · entry 2

Burgstahler David F · CIK 0001374179 · Director · President & CEO · 10% owner

Dean Thompson · CIK 0001069096 · Director · Executive Chairman · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 15,561,473

F3 · kind: The Reporting Persons acquired indirectly 3,278,154 shares of Class A common stock through Fund IV and 3,260,578 shares of Class A common stock through Offshore Fund IV, in each case, at an exchange ratio of 2.03 shares of the Issuer's Class A common stock for each share of common stock of Organogenesis Inc. in connection with the consummation of the business combination pursuant to that certain Agreement and Plan of Merger, dated as of August 17, 2018, by and among the Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis Inc.

F3 · price: The Reporting Persons acquired indirectly 3,278,154 shares of Class A common stock through Fund IV and 3,260,578 shares of Class A common stock through Offshore Fund IV, in each case, at an exchange ratio of 2.03 shares of the Issuer's Class A common stock for each share of common stock of Organogenesis Inc. in connection with the consummation of the business combination pursuant to that certain Agreement and Plan of Merger, dated as of August 17, 2018, by and among the Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis Inc.

F4 · balance_after: Represents 7,801,651 shares of Class A common stock indirectly owned by the Reporting Persons through Fund IV and 7,759,802 shares of Class A common stock indirectly owned by the Reporting Persons through Offshore Fund IV.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: David Burgstahler and Thompson Dean. Messrs. Burgstahler and Dean are managers of Avista Acquisition LLC, the sole shareholder of Avista Acquisition Corp. (the "Sponsor"), and are members of the investment committee of Avista Capital Partners IV GP, L.P., the general partner of Avista Capital Partners IV, L.P. ("Fund IV") and Avista Capital Partners (Offshore) IV, L.P. ("Offshore Fund IV"), and each has veto rights over the voting and disposition of the securities of the Issuer.

F8 · ownership.nature: Because of the relationship between the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001140361-18-045047 · form4.xml · nonDerivative · entry 1

Burgstahler David F · CIK 0001374179 · Director · President & CEO · 10% owner

Dean Thompson · CIK 0001069096 · Director · Executive Chairman · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 9,022,741

F2 · kind: The Reporting Persons acquired indirectly in a private placement from Avista Healthcare Public Acquisition Corp. (prior to the Issuer's Business Combination) an aggregate of 9,022,741 shares of Class A common stock, including 4,523,497 shares owned through Fund IV and 4,499,244 shares owned through Offshore Fund IV, and an aggregate of 4,100,000 warrants to purchase shares of Class A common stock, including 2,055,510 warrants to purchase 1,027,755 shares through Fund IV and 2,044,490 warrants to purchase 1,022,245 shares owned through Offshore Fund IV warrants to purchase one-half of one share of Class A common stock for an aggregate purchase price of $46,000,000.

F2 · price: The Reporting Persons acquired indirectly in a private placement from Avista Healthcare Public Acquisition Corp. (prior to the Issuer's Business Combination) an aggregate of 9,022,741 shares of Class A common stock, including 4,523,497 shares owned through Fund IV and 4,499,244 shares owned through Offshore Fund IV, and an aggregate of 4,100,000 warrants to purchase shares of Class A common stock, including 2,055,510 warrants to purchase 1,027,755 shares through Fund IV and 2,044,490 warrants to purchase 1,022,245 shares owned through Offshore Fund IV warrants to purchase one-half of one share of Class A common stock for an aggregate purchase price of $46,000,000.

F2 · balance_after: The Reporting Persons acquired indirectly in a private placement from Avista Healthcare Public Acquisition Corp. (prior to the Issuer's Business Combination) an aggregate of 9,022,741 shares of Class A common stock, including 4,523,497 shares owned through Fund IV and 4,499,244 shares owned through Offshore Fund IV, and an aggregate of 4,100,000 warrants to purchase shares of Class A common stock, including 2,055,510 warrants to purchase 1,027,755 shares through Fund IV and 2,044,490 warrants to purchase 1,022,245 shares owned through Offshore Fund IV warrants to purchase one-half of one share of Class A common stock for an aggregate purchase price of $46,000,000.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: David Burgstahler and Thompson Dean. Messrs. Burgstahler and Dean are managers of Avista Acquisition LLC, the sole shareholder of Avista Acquisition Corp. (the "Sponsor"), and are members of the investment committee of Avista Capital Partners IV GP, L.P., the general partner of Avista Capital Partners IV, L.P. ("Fund IV") and Avista Capital Partners (Offshore) IV, L.P. ("Offshore Fund IV"), and each has veto rights over the voting and disposition of the securities of the Issuer.

F8 · ownership.nature: Because of the relationship between the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001661181-18-000043 · edgar.xml · derivative · entry 4

Montecalvo Antonio S. · CIK 0001759261 · VP Health Policy & Contracting

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 101,500

Underlying: Common Stock · 101,500 shares

Expires 2027-05-04

F7 · price: Received in connection with the Merger in exchange for an option to acquire 50,000 shares of common stock of Organogenesis for $7.01 per share.

F6 · derivative.exercise_date: The shares underlying the option vested or shall vest 20% annually beginning on January 1, 2018.

SEC source: 0001661181-18-000043 · edgar.xml · derivative · entry 3

Montecalvo Antonio S. · CIK 0001759261 · VP Health Policy & Contracting

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,576

Underlying: Common Stock · 100,576 shares

Expires 2027-05-04

F5 · price: Received in connection with the Merger in exchange for an option to acquire 49,545 shares of common stock of Organogenesis for $7.01 per share.

F4 · derivative.exercise_date: The shares underlying the option vested or shall vest 20% annually beginning on December 31, 2017.

SEC source: 0001661181-18-000043 · edgar.xml · derivative · entry 2

Montecalvo Antonio S. · CIK 0001759261 · VP Health Policy & Contracting

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 30,450

Underlying: Common Stock · 30,450 shares

Expires 2020-02-22

F3 · price: Received in connection with the Merger in exchange for an option to acquire 15,000 shares of common stock of Organogenesis for $3.45 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000043 · edgar.xml · nonDerivative · entry 1

Montecalvo Antonio S. · CIK 0001759261 · VP Health Policy & Contracting

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,482

F1 · price: Received in connection with the Issuer's business combination (the "Merger") with Organogenesis Inc. ("Organogenesis") in accordance with the terms of the Agreement and Plan of Merger dated as of August 17, 2018 among the Issuer, which was then referred to as Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis, in exchange for 4,178 shares of common stock of Organogenesis.

SEC source: 0001661181-18-000054 · edgar.xml · derivative · entry 1

Tamaroff Joshua Alexander · CIK 0001705548 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 30,000

Underlying: Common Stock · 30,000 shares

Expires 2028-12-10

F1 · derivative.exercise_date: The option becomes exercisable in equal yearly installments over three years from the date of grant.

SEC source: 0001140361-18-045058 · form4.xml · derivative · entry 1

Avista Acquisition Corp. · CIK 0001661187 · 10% owner

Avista Acquisition, LLC · CIK 0001686388 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,048,691

Underlying: Class A Ordinary Shares · 3,247,668 shares

Expires not disclosed

F1 · derivative.exercise_price: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F2 · kind: The 3,247,668 Class B ordinary shares were forfeited by Avista Acquisition Corp. (the "Sponsor") to the Issuer for no consideration prior to the closing of the Business Combination.

F2 · price: The 3,247,668 Class B ordinary shares were forfeited by Avista Acquisition Corp. (the "Sponsor") to the Issuer for no consideration prior to the closing of the Business Combination.

F1 · derivative.exercise_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F1 · derivative.expiration_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F3 · ownership.direct: Directly owned by Sponsor. The sole shareholder of Sponsor is Avista Acquisition, LLC ("Avista Acquisition" and, together with Sponsor, the "Reporting Persons").

F4 · ownership.direct: Because of the relationship among the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any.

F5 · ownership.direct: Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001140361-18-045050 · form4.xml · derivative · entry 1

O'Neil Robert P · CIK 0001685002 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 69,571

Underlying: Class A Ordinary Shares · 243,896 shares

Expires not disclosed

F1 · derivative.exercise_price: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F2 · kind: 243,896 Class B ordinary shares were forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F2 · price: 243,896 Class B ordinary shares were forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F1 · derivative.exercise_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F1 · derivative.expiration_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

SEC source: 0001661181-18-000050 · edgar.xml · derivative · entry 1

Leibowitz Arthur S · CIK 0001467329 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 30,000

Underlying: Common Stock · 30,000 shares

Expires 2028-12-10

F1 · derivative.exercise_date: The option becomes exercisable in equal yearly installments over three years from the date of grant.

SEC source: 0001661181-18-000039 · edgar.xml · derivative · entry 1

Freedman Lori · CIK 0001410291 · VP and General Counsel

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 40,600

Underlying: Common Stock · 40,600 shares

Expires 2028-02-21

F2 · price: Received in connection with the Issuer's business combination (the "Merger") with Organogenesis Inc. ("Organogenesis") in accordance with the terms of the Agreement and Plan of Merger dated as of August 17, 2018 among the Issuer, which was then referred to as Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis, in exchange for an option to acquire 20,000 shares of common stock of Organogenesis for $10.95 per share.

F1 · derivative.exercise_date: The shares underlying the option vested or shall vest 20% annually beginning on January 30, 2018.

SEC source: 0001140361-18-045055 · form4.xml · derivative · entry 1

MARKISON BRIAN A · CIK 0001283061 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 133,589

Underlying: Class A Ordinary Shares · 442,151 shares

Expires not disclosed

F1 · derivative.exercise_price: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F2 · kind: 442,151 Class B ordinary shares were forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F2 · price: 442,151 Class B ordinary shares were forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F1 · derivative.exercise_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F1 · derivative.expiration_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

SEC source: 0001661181-18-000049 · edgar.xml · nonDerivative · entry 3

NUSSDORF GLENN H · CIK 0001244191 · Director · 10% owner

Wisdom Starr · CIK 0001760694 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,846,723

F5 · price: Received by Glenn H. Nussdorf in connection with the Merger in exchange for 90,069 shares of common stock of Organogenesis previously held by Mr. Nussdorf.

F6 · ownership.direct: The reported securities are held directly by Glenn H. Nussdorf, who is a member of the Group.

SEC source: 0001661181-18-000049 · edgar.xml · nonDerivative · entry 2

NUSSDORF GLENN H · CIK 0001244191 · Director · 10% owner

Wisdom Starr · CIK 0001760694 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 67,663,882

F3 · price: Received by Albert Erani in connection with the Merger in exchange for 385,174 shares of common stock of Organogenesis previously held by Mr. Erani.

F4 · ownership.direct: The reported securities are held directly by Albert Erani, who is a member of the Group.

SEC source: 0001661181-18-000049 · edgar.xml · nonDerivative · entry 1

NUSSDORF GLENN H · CIK 0001244191 · Director · 10% owner

Wisdom Starr · CIK 0001760694 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 66,881,978

F1 · price: Received by Alan A. Ades in connection with the Issuer's business combination (the "Merger") with Organogenesis Inc. ("Organogenesis") in accordance with the terms of the Agreement and Plan of Merger dated as of August 17, 2018 among the Issuer, which was then referred to as Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis, in exchange for 3,093,320 shares of common stock of Organogenesis previously held by Mr. Ades.

F2 · ownership.direct: The reported securities are held directly by Alan A. Ades, who is a member of the Group (as defined below).

SEC source: 0001661181-18-000052 · edgar.xml · derivative · entry 1

MACKIE WAYNE D · CIK 0001240034 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 30,000

Underlying: Common Stock · 30,000 shares

Expires 2028-12-10

F1 · derivative.exercise_date: The option becomes exercisable in equal yearly installments over three years from the date of grant.

SEC source: 0001140361-18-045056 · form4.xml · derivative · entry 1

Bjorklund Hakan · CIK 0001583056 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 69,571

Underlying: Class A Ordinary Shares · 243,896 shares

Expires not disclosed

F1 · derivative.exercise_price: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F2 · kind: 243,896 Class B ordinary shares were forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F2 · price: 243,896 Class B ordinary shares were forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F1 · derivative.exercise_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F1 · derivative.expiration_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

SEC source: 0001140361-18-045052 · form4.xml · derivative · entry 1

Harwood Charles C Jr · CIK 0001624072 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 69,571

Underlying: Class A Ordinary Shares · 243,896 shares

Expires not disclosed

F1 · derivative.exercise_price: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F2 · kind: 243,896 Class B ordinary shares forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F2 · price: 243,896 Class B ordinary shares forfeited to the Issuer for no consideration prior to the closing of the Business Combination.

F1 · derivative.exercise_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

F1 · derivative.expiration_date: Pursuant to the Amended and Restated Memorandum and Articles of Association (the "Articles") of Avista Healthcare Public Acquisition Corp. (the "Issuer"), the Class B ordinary shares, par value $0.0001 per share (the "Class B Shares") will automatically convert into Class A ordinary shares, par value $0.0001 per share, of the Issuer at the time of the Issuer's Business Combination, as defined in the Articles, on a one-for-one basis, subject to adjustment, and have no expiration date.

SEC source: 0001140361-18-045048 · form4.xml · nonDerivative · entry 1

Avista Capital Managing Member IV, LLC · CIK 0001761175 · 10% owner

Avista Capital Partners (Offshore) IV, L.P. · CIK 0001664173 · 10% owner

Avista Capital Partners IV, L.P. · CIK 0001664176 · 10% owner

Avista Capital Partners IV GP, L.P. · CIK 0001761195 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Notes

Disclosed balance after: 15,561,473

F2 · kind: Represents 3,278,154 shares of Class A common stock received by Fund IV and 3,260,578 shares of Class A common stock received by Offshore Fund IV, in each case, at an exchange ratio of 2.03 shares of the Issuer's Class A common stock for each share of common stock of Organogenesis Inc. in connection with the consummation of the business combination pursuant to that certain Agreement and Plan of Merger, dated as of August 17, 2018, by and among Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis Inc.

F2 · shares: Represents 3,278,154 shares of Class A common stock received by Fund IV and 3,260,578 shares of Class A common stock received by Offshore Fund IV, in each case, at an exchange ratio of 2.03 shares of the Issuer's Class A common stock for each share of common stock of Organogenesis Inc. in connection with the consummation of the business combination pursuant to that certain Agreement and Plan of Merger, dated as of August 17, 2018, by and among Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis Inc.

F2 · price: Represents 3,278,154 shares of Class A common stock received by Fund IV and 3,260,578 shares of Class A common stock received by Offshore Fund IV, in each case, at an exchange ratio of 2.03 shares of the Issuer's Class A common stock for each share of common stock of Organogenesis Inc. in connection with the consummation of the business combination pursuant to that certain Agreement and Plan of Merger, dated as of August 17, 2018, by and among Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis Inc.

F3 · balance_after: Because of the relationship among the Reporting Persons, the Reporting Persons may be deemed to beneficially own the securities reported herein to the extent of their respective pecuniary interests. Each Reporting Person disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any.

F1 · ownership.nature: This statement is being filed by the following Reporting Persons: Avista Capital Partners IV, L.P. ("Fund IV"), Avista Capital Partners (Offshore) IV, L.P. ("Offshore Fund IV"), Avista Capital Partners IV GP, L.P. ("Fund IV GP"), which is the general partner of Fund IV and Offshore Fund IV; and Avista Capital Managing Member IV, LLC, which is the general partner of Fund IV GP.

F4 · ownership.nature: Pursuant to Rule 16a-1(a)(4) under the Exchange Act, this filing shall not be deemed an admission that the Reporting Persons are, for purposes of Section 16 of the Exchange Act or otherwise, the beneficial owners of any equity securities in excess of their respective pecuniary interests.

SEC source: 0001661181-18-000045 · edgar.xml · derivative · entry 2

Walthall Howard · CIK 0001759244 · Exec. VP, Strat. & Mkt Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 203,000

Underlying: Common Stock · 203,000 shares

Expires 2027-05-04

F4 · price: Received in connection with the Merger in exchange for an option to acquire 100,000 shares of common stock of Organogenesis for $7.01 per share.

F3 · derivative.exercise_date: The shares underlying the option shall vest 20% annually beginning on December 31, 2018.

SEC source: 0001661181-18-000045 · edgar.xml · derivative · entry 1

Walthall Howard · CIK 0001759244 · Exec. VP, Strat. & Mkt Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 85,710

Underlying: Common Stock · 85,710 shares

Expires 2027-05-04

F2 · price: Received in connection with the Issuer's business combination (the "Merger") with Organogenesis Inc. ("Organogenesis") in accordance with the terms of the Agreement and Plan of Merger dated as of August 17, 2018 among the Issuer, which was then referred to as Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis, in exchange for an option to acquire 42,222 shares of common stock of Organogenesis for $7.01 per share.

F1 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 11

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,900

Underlying: Common Stock · 60,900 shares

Expires 2027-05-04

F16 · price: Received in connection with the Merger in exchange for an option to acquire 30,000 shares of common stock of Organogenesis for $7.01 per share.

F15 · derivative.exercise_date: The shares underlying the option vested or shall vest 20% annually beginning on January 1, 2018.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 10

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 102,200

Underlying: Common Stock · 102,200 shares

Expires 2027-05-04

F14 · price: Received in connection with the Merger in exchange for an option to acquire 50,345 shares of common stock of Organogenesis for $7.01 per share.

F13 · derivative.exercise_date: The shares underlying the option vested or shall vest 20% annually beginning on December 31, 2017.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 9

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 30,450

Underlying: Common Stock · 30,450 shares

Expires 2024-04-10

F12 · price: Received in connection with the Merger in exchange for an option to acquire 15,000 shares of common stock of Organogenesis for $2.38 per share.

F11 · derivative.exercise_date: The shares underlying the option vested or shall vest 20% annually beginning on April 1, 2015.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 8

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,060

Underlying: Common Stock · 4,060 shares

Expires 2025-08-11

F10 · price: Received in connection with the Merger in exchange for an option to acquire 2,000 shares of common stock of Organogenesis for $5.00 per share.

F9 · derivative.exercise_date: The shares underlying the option vested or shall vest 25% annually beginning on August 11, 2016.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 7

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 958

Underlying: Common Stock · 958 shares

Expires 2025-01-12

F8 · price: Received in connection with the Merger in exchange for an option to acquire 472 shares of common stock of Organogenesis for $2.50 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 6

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 805

Underlying: Common Stock · 805 shares

Expires 2023-07-17

F7 · price: Received in connection with the Merger in exchange for an option to acquire 397 shares of common stock of Organogenesis for $9.10 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 5

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 805

Underlying: Common Stock · 805 shares

Expires 2022-08-21

F6 · price: Received in connection with the Merger in exchange for an option to acquire 397 shares of common stock of Organogenesis for $2.95 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 4

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 958

Underlying: Common Stock · 958 shares

Expires 2021-10-17

F5 · price: Received in connection with the Merger in exchange for an option to acquire 472 shares of common stock of Organogenesis for $2.92 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 3

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,151

Underlying: Common Stock · 1,151 shares

Expires 2020-04-15

F4 · price: Received in connection with the Merger in exchange for an option to acquire 567 shares of common stock of Organogenesis for $3.45 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · derivative · entry 2

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 667

Underlying: Common Stock · 667 shares

Expires 2019-10-02

F3 · price: Received in connection with the Merger in exchange for an option to acquire 329 shares of common stock of Organogenesis for $3.45 per share.

F2 · derivative.exercise_date: 100% of the shares subject to this option are fully vested and exercisable.

SEC source: 0001661181-18-000041 · edgar.xml · nonDerivative · entry 1

Grow Brian · CIK 0001759142 · Chief Commercial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,462

F1 · price: Received in connection with the Issuer's business combination (the "Merger") with Organogenesis Inc. ("Organogenesis") in accordance with the terms of the Agreement and Plan of Merger dated as of August 17, 2018 among the Issuer, which was then referred to as Avista Healthcare Public Acquisition Corp., Avista Healthcare Merger Sub, Inc. and Organogenesis, in exchange for 720 shares of common stock of Organogenesis.