Exhibit 99.1

22C Capital I, L.P.

By: 22C Capital GP I, L.L.C., its general partner

By: 22C Capital GP I MM LLC, its managing member

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Member

Date: 06/04/2020

22C DiscoverOrg Advisors, LLC

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Managing Member

Date: 06/04/2020

22C DiscoverOrg Investors, LLC

By: 22C DiscoverOrg MM, LLC, its managing member

By: 22C DiscoverOrg Advisors, LLC, its managing member

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Managing Member

Date: 06/04/2020

22C Magellan Holdings LLC

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Officer with Title of Authorized Signatory

Date: 06/04/2020

22C Capital GP I MM LLC

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Member

Date: 06/04/2020

22C Capital GP I, L.L.C.

By: 22C Capital GP I MM LLC, its managing member

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Member

Date: 06/04/2020

Ex. A-1

22C DiscoverOrg MM, LLC

By: 22C DiscoverOrg Advisors, LLC, its managing member

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Managing Member

Date: 06/04/2020

22C Capital I-A, L.P

By: 22C Capital GP I, L.L.C., its general partner

By: 22C Capital GP I MM LLC, its managing member

By: /s/ Eric J. Edell

Name: Eric J. Edell

Title: Managing Member

Date: 06/04/2020

Ex. A-2

22C Magellan Holdings LLC 3