| Sector | Domains | MX % | SPF % | DMARC % | Proxy % | DMARC Rate |
|---|---|---|---|---|---|---|
| Large Enterprise | 26,334 | 95.0% | 93.4% | 75.3% | 29.7% | |
| Education | 4,199 | 91.5% | 83.2% | 60.7% | 11.1% | |
| Nonprofit | 84,272 | 91.3% | 80.1% | 54.9% | 11.4% | |
| Government | 32,710 | 86.9% | 81.2% | 52.2% | 17.1% | |
| Other Business | 29,576 | 90.8% | 80.6% | 47.1% | 13.6% | |
| Small Business | 244,137 | 90.9% | 82.2% | 44.9% | 12.5% |
Infrastructure drives adoption: Large enterprises use email security proxies at 29.7% — more than 2× the rate of government (17.1%) or small business (12.5%). This proxy advantage explains much of the 30pp DMARC gap. The pattern is consistent across all sectors: gateway adoption = better authentication posture.
| Source | Domains | Coverage |
|---|---|---|
| SAM.gov Entity Registration | 375,124 | Federal contractors, grantees, registrants |
| Public Entity Database | 35,855 | State/local government, education, special districts |
| Small Business Dataset | 10,935 | Supplemental small-business domains |
| Total Unique | 406,680 | After deduplication (13,210 overlaps removed) |
| Segment | Proxied SPF | Non-Proxied SPF |
|---|---|---|
| Small Business | 99.4% | 85.1% |
| Public Entities | 97.3% | 89.2% |
| Segment | Proxied DMARC | Non-Proxied DMARC |
|---|---|---|
| Small Business | 61.1% | 54.6% |
| Public Entities | 75.7% | 53.0% |