The HDF Group
Donations deductibleRevenue
$3m
year to 31 December 2025
Expenses
$3.2m
year to 31 December 2025
Total assets
$2.1m
$441k liabilities
Net assets
$1.6m
assets less liabilities
Directors and trustees
3
7.4 years on average
Staff
21
employees, year to 31 December 2025
Left since last filing
0
no seats appear to have opened
Officers and senior staff
15
named in Part VII
The HDF Group's network
3 peoplei3 people on this map.The large node is the subject of this page. Solid lines are what the register itself records (3). Form 990 filings give names without a person identifier; SEC insider filings carry a CIK.The board
3 listediTime on the board is observed from the annual filings: the IRS files no appointment date, so the bar counts years from the first filing the person appears on - a lower bound, not a filed start date. Names are exactly as filed. The IRS publishes no person identifier, so this edition does not yet link a person across organisations.Time served and departures are observed across annual filings. Observed time served is a lower bound - a member may have joined before the first year on record. The organisation reported 3 voting members of its governing body on its latest Form 990 Part VI, which matches the board listed here.| Name | Role as filed | Since | On the board |
|---|---|---|---|
| Easwaran G Nadhan | Director | 2021 | 5 yrs |
| Jessica Popp | President | 2018 | 8 yrs |
| Michael J Folk | Secretary/Treasurer | 2018 | 8 yrs |
Under 5 years5 to 6 years6 years or more
Officers and senior leadership
15 listediNamed in Part VII as officers, key employees or highest-compensated staff - not board members, shown for completeness.| Name | Title as filed | On the filings |
|---|---|---|
| Aleksandar Jelenak | Software Engineer | since 2018 |
| Dana Robinson | Senior Software Engineer | since 2018 |
| DAX Rodriguez | Dir. of Commercial Services & Solutions | since 2018 |
| Gerd Heber | HDF5 Database and High Performance Computing Leade | since 2018 |
| Jerome Soumagne | HPC Software Developer | 2019 |
| John Mainzer | Senior Software Engineer | since 2018 |
| John Readey | Director of Tools and Cloud Technology | since 2018 |
| Melinda Eads | Employee | since 2023 |
| Michael Breitenfeld | Employee | since 2022 |
| Muqun Yang | Employee | 2022 |
| Neelam Bagha | Employee | since 2022 |
| Neil Fortner | Employee | since 2023 |
| Ray Habermann | Director of Earth Science | 2018 |
| Tom Brady | Dir. of Federal Business Development | 2018 |
| Vanisha Taylor | Dir. of Business & Finance | since 2018 |
Pay and hours
year to 31 December 2025iFrom Part VII of the Form 990: compensation reported for each officer, director, trustee, key employee and highest-paid staff member, and the average hours a week they report. Most board members are unpaid; a blank means nothing was reported. Pay from related organisations is shown separately.| Name | Title as filed | Hours a week | Pay from the organisation | Related organisations | Other |
|---|---|---|---|---|---|
| Gerd Heber | Executive Director | 40 | $187k | $22k | |
| John Readey | Director of Tools and Cloud | 40 | $186k | $22k | |
| Aleksandar Jelenak | Employee | 40 | $157k | $1k | |
| Vanisha Taylor | CFO | 40 | $157k | $14k | |
| Michael Breitenfeld | Employee | 40 | $154k | $15k | |
| Neelam Bagha | Employee | 40 | $143k | $7k | |
| Neil Fortner | Employee | 40 | $133k | $30k | |
| Melinda Eads | Employee | 40 | $126k | $15k | |
| Jessica Popp | President | 1 | $4k | ||
| Easwaran G Nadhan | Director | 1 | $4k | ||
| Michael J Folk | Secretary/Treasurer | 1 | $0 |
About
- Legal name
- The HDF Group
- EIN
- 680600605
- Address
- 410 E University Ave Ste 200, Champaign, IL, 61820-3871
- State
- Illinois
- Mission
- The organization's primary exempt purpose is to ensure the sustainability of hdf technologies and ongoing accessibility of hdf-stored data for the government agencies and organizations that have mission-critical systems relying on hdf. Specifically, the organization's mission is to develop and maintain free, open source computer applications that move and store scientific and complex data... (as filed on the Form 990)
- Activity (NTEE)
- U41 Science and technology research
- IRS classification
- 501(c)03 (tax-exempt under section 501(c)(3) where shown)
- Classified purpose
- Science & Technology
- Size band
- 6 (IRS master file code)
- Formed
- 2004
- Principal officer
- Gerd Heber (as named on the Form 990)
- IRS ruling date
- 1 August 2006
- Status
- Code 01 (unconditional exemption)
- Form 990 filings on record
- 7, latest 2025
- IRS Publication 78
- PC (contributions deductible)
Most connected
Longest observed on the filings
≥8years on the filingsJessica Popp
≥8years on the filingsMichael J Folk
≥5years on the filingsEaswaran G Nadhan
Latest return
year to 31 December 2025iFigures from the newest Form 990 or 990-EZ in the IRS e-file releases of 2025 and 2026, for the year ending 31 December 2025. US dollars, as filed.- Total assets
- $2.1m
- Total liabilities
- $441k
- Net assets or fund balances
- $1.6m
- Contributions and grants received
- $13k
- Program service revenue
- $2.8m
- Employees
- 21