Combinatorics Consortium Inc
Nonprofit profile at a glance
- EIN
- 862621132
- IRS 990-EZ coverage
- 2021–2025
- Forms available
- Form 990-EZ 2025
- Location
- Minneapolis, MN, USA
- Phone
- 6126256682
- Rating
- 49
- Verdict
- MIXED
- Rating confidence
- Moderate
- Sector
- Support N.E.C.
Reported finances
- Revenue
- $29,679
- Expenses
- $41,443
- Assets
- $152,157
- Liabilities
- $0
Source: IRS Form 990-EZ. Selected filing: tax year 2025. Amounts in USD.
Leadership & pay
4 people listed
Executive titles in this filing
- Sara Billey (President)
- Volkmar Welker (Vice President)
People named in this filing
- Victor Reiner (Treasurer)
- Sara Billey (President)
- Volkmar Welker (Vice President)
Selected names, not a complete roster or a statement of current roles. Open leadership details for the complete filed list.
Source: IRS Form 990-EZ. Selected filing: tax year 2025. Names and roles reflect this filing, not necessarily current officeholders.
Overview
Mission
Publishing, supporting conferences, support research
What it reported doing in 2025
Conference support - grants to conferences GSCC 25, BadMath 2025, CAAC 2025, alternating sign matrices, 31st British Combinatorial Conference, CAAC 2026, FPSAC 2025,
Operating model
- Revenue model
- Donor-supported. 100% of the money available for current operations came from contributions and gifts.
- Distribution model
- Cannot be determined from the filing. The filing does not provide enough consistent spending detail to tell whether the nonprofit works directly or through others.
The verdict
MIXED - The filed numbers largely add up and program spending has grown recently. A relatively small share of available resources goes toward mission work and a relatively small share of total spending goes to programs.
Rating breakdown
- Financial Efficiency: 8
- Transparency & Controls: 100
- Sustainability: 44
- Growth: 60
Detailed rating inputs
Financial Efficiency
- Mission deployment rate: 9.3%; rating input score 9
- Program expense ratio: 6.6%; rating input score 7
Transparency & Controls
- Consistency checks: 100%; rating input score 100; 51st percentile among comparable filings
- Major donor itemization: Yes; rating input score 100
Sustainability
- Operating margin: -39.6%; rating input score 14; 14th percentile among comparable filings
- Total-asset coverage ratio: 3.67; rating input score 78; 78th percentile among comparable filings
- Liabilities to assets ratio: 0; rating input score 66; 66th percentile among comparable filings
- Officer compensation ratio: 0%; rating input score 56; 56th percentile among comparable filings
Growth
- Program expense growth: 34.8% per year; rating input score 100; 88th percentile among comparable filings
- Revenue growth: -33.3% per year; rating input score 0; 9th percentile among comparable filings
- Asset growth: 6% per year; rating input score 100; 60th percentile among comparable filings
Details
- Where the money goes: 9.3% of revenue deployed · 6.6% of spending went to programs
- Governance: Filed governance answers
- Accomplishments: 3 filed program accomplishments · $3K in reported program spending
- Leadership: top reported pay $0 · 4 people listed
- Consistency: 8 of 9 current checks pass · 1 finding to review
- Schedules: 3 filed schedules
- Filing history: 5 filing years from 2021 to 2025
- Contacts: How to reach this organization
- Grant readiness: Federal tax and exclusion status, award history, and grant-maker relationships.
- People: Everyone the filings name, and which of them the filings identify by more than a name.
Key Signals
Signals prioritize questions for review. They are not findings of misconduct.
- High — Financial Efficiency: Mission deployment rate scored 9/100.
- High — Financial Efficiency: Program expense ratio scored 7/100.
- Moderate — Transparency & Controls: Part III transfer expenses within program total did not reconcile in the filed values.
- High — Sustainability: Operating margin scored 14/100.
- High — Growth: Revenue growth scored 0/100.
- Review — Sustainability: Officer compensation ratio scored 56/100.