# Core Bond Fund

Core Bond Fund is a registered fund series of ULTRA SERIES FUND (series S000019978). Net assets $49.8M as of 2026-03-31.

## Profile

- Series ID: S000019978
- Registrant: ULTRA SERIES FUND
- LEI: 254900ZJ8847WPVD2X76
- Net assets: $49.8M
- Total assets: $50.1M
- As of: 2026-03-31

## Advisers

- [Madison Asset Management, LLC (Advisor)](https://search.stillhousedata.com/firm/130874)

## Top holdings (200 reported)

_Showing 15 of 200 holdings by value._

| Holding | Ticker | Value | % of fund |
| --- | --- | --- | --- |
| [Freddie Mac](https://search.stillhousedata.com/security/31334YPZ4) | — | $1.1M | 228.22% |
| [United States Treasury](https://search.stillhousedata.com/security/912810UC0) | — | $898K | 180.22% |
| [United States Treasury](https://search.stillhousedata.com/security/912810PX0) | — | $756K | 151.74% |
| [Freddie Mac](https://search.stillhousedata.com/security/3132DVL94) | — | $751K | 150.76% |
| [United States Treasury](https://search.stillhousedata.com/security/912810QS0) | — | $670K | 134.42% |
| [State Street Global Advisors](https://search.stillhousedata.com/security/857492706) | — | $635K | 127.48% |
| [Fannie Mae](https://search.stillhousedata.com/security/3140QPA56) | — | $581K | 116.53% |
| [United States Treasury](https://search.stillhousedata.com/security/91282CHR5) | — | $572K | 114.75% |
| [United States Treasury](https://search.stillhousedata.com/security/912810RM2) | — | $572K | 114.75% |
| [Fannie Mae](https://search.stillhousedata.com/security/3140QP2R7) | — | $568K | 114.02% |
| [United States Treasury](https://search.stillhousedata.com/security/91282CKQ3) | — | $556K | 111.59% |
| [United States Treasury](https://search.stillhousedata.com/security/912810UB2) | — | $549K | 110.18% |
| [Fannie Mae](https://search.stillhousedata.com/security/3140QPHX8) | — | $523K | 105.04% |
| [United States Treasury](https://search.stillhousedata.com/security/912810EZ7) | — | $513K | 102.86% |
| [Freddie Mac](https://search.stillhousedata.com/security/3132DNB51) | — | $506K | 101.61% |

## Net asset history

| Report date | Net assets |
| --- | --- |
| 2026-03-31 | $49.8M |
| 2025-12-31 | $51.8M |
| 2025-09-30 | $53.2M |
| 2025-06-30 | $53.8M |
| 2025-03-31 | $64.7M |
| 2024-12-31 | $65.3M |
| 2024-09-30 | $69.5M |
| 2024-06-30 | $67.5M |

## More

- [Registrant: ULTRA SERIES FUND](https://search.stillhousedata.com/registrant/732697)
- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/fund/S000019978.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.