As we first noted on March 31, 2026, Gaetan Poirier joined Alexander Mackey and Jay Mitchell on the portfolio management team of the MFS Corporate Bond and MFS Meridian US Corporate Bond on that date. Poirier will retain his role as head of credit research and will no longer have direct analyst responsibilities. MFS indicates the strategy’s investment philosophy, process, and day-to-day implementation will remain unchanged. As head of credit research, Poirier oversees global investment-grade, high-yield, and emerging-market corporate research teams. He joined MFS in 1999 and spent most of his career as a high-yield research analyst before assuming his current leadership role in April 2023. Mackey, Mitchell, and Poirier have worked together throughout their careers at MFS, supporting continuity in decision-making and collaboration. The addition follows a deliberate and thoughtful process amid growth across MFS’ fixed-income platform and reflects an effort to institutionalize resources and deepen leadership. The existing team remains a key strength. Since joining the roster in 2017, Mackey has kept the strategy aligned with MFS’ hallmark, fundamentals-driven approach and measured risk-taking, despite his 2023 promotion to co-CIO. The addition of Mitchell in 2023 further strengthened the bench; although relatively new to portfolio management, his two decades of credit research experience have translated into sound judgment. Poirier’s appointment further reinforces this depth without altering roles or responsibilities materially. Overall, the team and investment approach continue to merit Above Average People and Above Average Process Pillar ratings, supported by strong leadership, disciplined execution, and a durable, team-based investment framework.
MFS Corporate Bond Fund Class R6 MFBKX
- NAV / 1-Day Return 12.38 / +0.08 %
- Total Assets 4.4B
-
Adj. Expense Ratio
0.420%
- Expense Ratio 0.420%
- Distribution Fee Level Average
- Share Class Type Retirement, Large
- Category Corporate Bond
- Credit Quality / Interest Rate Sensitivity Medium/Moderate
- Min. Initial Investment 0
- Status Open
- TTM Yield 4.87%
- Effective Duration 6.60 years
USD | NAV as of Jun 16, 2026 | 1-Day Return as of Jun 16, 2026, 1:30 AM GMT+0
Morningstar’s Analysis MFBKX
Will MFBKX outperform in the future?
Get our overall rating based on a fundamental assessment of the pillars below.
People Pillar
The People Pillar is our evaluation of the MFBKX management team’s experience and ability. We find that high-quality management teams deliver superior performance relative to their benchmarks and/or peers.
Parent Pillar
The Parent Pillar is our rating of MFBKX’s parent organization’s priorities and whether they’re in line with investors’ interests.
- Current Portfolio Date
- Equity Holdings —
- Bond Holdings —
- Other Holdings —
- % Assets in Top 10 Holdings 8.3
|
Top 10 Holdings
|
% Portfolio Weight
|
Market Value USD
|
Sector
|
|---|---|---|---|
US Treasury Bond Future June 26 | 2.66 | 117M | Government |
2 Year Treasury Note Future June 26 | 2.01 | 88M | Government |
Ultra US Treasury Bond Future June 26 | 1.97 | 87M | Government |
Currency Cash CASH_USD | 1.35 | 59M | Cash and Equivalents |
UBS Group AG 3.13% | 0.78 | 34M | Corporate |
JPMorgan Chase & Co. 2.55% | 0.77 | 34M | Corporate |
Boeing Co. 5.81% | 0.76 | 34M | Corporate |
The Charles Schwab Corporation 4.91% | 0.63 | 28M | Corporate |
Bermuda (Government of) 5% | 0.59 | 26M | Government |
Morgan Stanley 5.07% | 0.58 | 26M | Corporate |