| 2023 | Steel Fabricators Association of So California | 990EZ | Treasurer | 1 | $0 | $0 | View return |
| 2023 | Carbon Forestry Trust Inc. | 990 | President | 2 | $0 | $0 | View return |
| 2022 | Carbon Forestry Trust Inc. | 990EZ | President | 2 | $0 | $0 | View return |
| 2022 | Steel Fabricators Association of So California | 990EZ | Treasurer | 0.5 | $0 | $0 | View return |
| 2022 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2021 | Carbon Forestry Trust Inc. | 990EZ | President | 1 | $0 | $0 | View return |
| 2021 | Steel Fabricators Association of So California | 990EZ | Treasurer | 1 | $0 | $0 | View return |
| 2021 | John Oster Family Foundation Inc. | 990PF | Trustee | 0 | $0 | $0 | View return |
| 2021 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2020 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2020 | Steel Fabricators Association of So California | 990EZ | Treasurer | 1 | $0 | $0 | View return |
| 2019 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2019 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2019 | Pi Kappa Alpha Fraternity - Theta Psi Chapman University | 990EZ | Historian | 0 | $0 | - | View return |
| 2019 | Agricultural Retailers Association | 990 | Past Chair Until Dec. 2019 | 2 | $0 | $0 | View return |
| 2018 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2018 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2017 | American Legion Post 002 John Regan | 990EZ | Sergeant Of Arms | 1 | $0 | $0 | View return |
| 2017 | John Oster Family Foundation Inc. | 990PF | Trustee | 0 | $0 | $0 | View return |
| 2017 | Agricultural Retailers Association | 990 | Chairman | 2 | $0 | $0 | View return |
| 2017 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2016 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2016 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2016 | Agricultural Retailers Association | 990 | Chairman-Elect | 2 | $0 | $0 | View return |
| 2015 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2015 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2015 | Agricultural Retailers Association | 990 | Vice Chairman | 2 | $0 | $0 | View return |
| 2014 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2014 | American Legion Post 002 John Regan | 990EZ | Asst Sgt At Arms | 2 | $0 | $0 | View return |
| 2014 | Agricultural Retailers Association | 990 | Director | 2 | $0 | $0 | View return |
| 2014 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2013 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2013 | Agricultural Retailers Association | 990 | Director | 2 | $0 | $0 | View return |
| 2013 | Choroideremia Research Foundation Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2012 | John Oster Family Foundation Inc. | 990PF | Trustee | 1 | $0 | $0 | View return |
| 2011 | John Oster Family Foundation Inc. | 990PF | Trustee | 2 | $0 | $0 | View return |