William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.

William Ryan is the Acting Director of the PCAOB’s Division of Enforcement and Investigations (DEI). In this role, he oversees and directs the PCAOB’s investigations and enforcement of violations of its rules, professional standards, and other applicable securities regulations.

Before his appointment as DEI’s Acting Director in December 2025, Mr. Ryan was DEI’s Chief Counsel, a role to which he was named in 2023. Mr. Ryan joined the PCAOB in January 2007 and was promoted to become a DEI Deputy Director in 2012.

Prior to joining the PCAOB, Mr. Ryan served for eight years as an Assistant Director and trial attorney in the Commercial Litigation Branch of the Department of Justice’s Civil Division. At the Justice Department, he represented the United States at trial and on appeal in complex commercial matters.

Mr. Ryan also has worked as a teaching fellow at Columbia Law School and as a law clerk for U.S. District Court Judge Nathaniel M. Gorton.

He received a B.A., summa cum laude, from Tufts University and a J.D. and LL.M. from Columbia Law School.