# Diamondback Energy Inc DIAMONDBACK ENER

Diamondback Energy Inc DIAMONDBACK ENER is a security (CUSIP 25278XAZ2) tracked across SEC portfolio filings. 15 registered fund positions totaling $40.8M via N-PORT as of 2026-05-31.

## Summary

- Issuer: Diamondback Energy Inc
- Class: DIAMONDBACK ENER
- CUSIP: 25278XAZ2
- Asset category: DBT
- 13F holders: 0
- N-PORT fund positions: 15
- N-PORT value: $40.8M
- N-PORT report: 2026-05-31

## Top fund holders (N-PORT)

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [VANGUARD WELLINGTON FUND](https://search.stillhousedata.com/fund/S000004406) | VANGUARD WELLINGTON FUND | $19.0M | 1.53% |
| [T. Rowe Price New Income Fund, Inc.](https://search.stillhousedata.com/fund/S000002136) | T. ROWE PRICE NEW INCOME FUND, INC. | $10.0M | 5.73% |
| [MFS Total Return Fund](https://search.stillhousedata.com/fund/S000002439) | MFS Series Trust V | $4.5M | 6.09% |
| [T. Rowe Price Corporate Income Fund, Inc.](https://search.stillhousedata.com/fund/S000002128) | T. ROWE PRICE CORPORATE INCOME FUND, INC. | $1.7M | 61.32% |
| [BlackRock Total Return Fund](https://search.stillhousedata.com/fund/S000004071) | BlackRock Bond Fund, Inc. | $1.3M | 0.72% |
| [MFS Total Return Series](https://search.stillhousedata.com/fund/S000002670) | MFS VARIABLE INSURANCE TRUST | $1.3M | 6.26% |
| [Core Bond Portfolio](https://search.stillhousedata.com/fund/S000005237) | Core Bond Portfolio | $832K | 11.07% |
| [T. Rowe Price Total Return Fund](https://search.stillhousedata.com/fund/S000055582) | T. ROWE PRICE TOTAL RETURN FUND, INC. | $668K | 10.98% |
| [HARTFORD TOTAL RETURN BOND HLS FUND](https://search.stillhousedata.com/fund/S000003222) | HARTFORD SERIES FUND INC | $533K | 3.97% |
| [Insight Select Income Fund](https://search.stillhousedata.com/fund/S000000000) | Insight Select Income Fund | $376K | 20.17% |
| [T. Rowe Price Spectrum Moderate Growth Allocation Fund](https://search.stillhousedata.com/fund/S000002138) | T. ROWE PRICE SPECTRUM FUNDS II, INC. | $169K | 0.39% |
| [GuideMark Core Fixed Income Fund](https://search.stillhousedata.com/fund/S000006189) | GPS Funds I | $147K | 8.54% |
| [ELFUN INCOME FUND](https://search.stillhousedata.com/fund/S000011831) | ELFUN INCOME FUND | $83K | 7.30% |
| [BlackRock Total Return V.I. Fund](https://search.stillhousedata.com/fund/S000062377) | BlackRock Variable Series Funds II, Inc. | $63K | 0.64% |
| [ELFUN DIVERSIFIED FUND](https://search.stillhousedata.com/fund/S000011823) | ELFUN DIVERSIFIED FUND | $34K | 1.86% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/25278XAZ2.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.