Ultra-Short Duration Bond Fund

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Ruta Ziverte

Head of fixed income for William Blair Investment Management and portfolio manager for the Low Duration, Core Fixed Income, Sustainable Fixed Income, and Intermediate Fixed Income strategies. In this role, she is responsible for developing and executing our fixed-income growth strategy (in conjunction with other members of the team), team leadership, and select portfolio management. Before joining William Blair, Ruta worked at Oppenheimer Funds, where she was the portfolio manager for the Global High Yield Fund and co-portfolio manager for the Global Strategic Income Fund. She also led a team of fixed-income credit analysts. Before joining Oppenheimer Funds in 2015, Ruta worked at GE Asset Management, where she most recently served as executive managing director and high-yield portfolio manager. Previously at GE, Ruta was a team leader and senior analyst, co-managing a leveraged finance research team, and was responsible for developing and implementing the firm's credit processes and procedures. Earlier in her career, Ruta was a credit analyst with Citigroup/Travelers Life and Annuity. She also worked at Phoenix Investment Partners. Ruta received a B.S. in business administration from the University of Latvia and an M.B.A. from Rensselaer Polytechnic Institute.

Education: B.S. in business administration from the University of Latvia; M.B.A. from Rensselaer Polytechnic Institute

Tenure with William Blair: Since 2019

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Vesta Marks, CFA, CAIA

Portfolio Manager for William Blair's Core Fixed Income and Low Duration Fixed Income strategies. Before joining William Blair, Vesta worked at Tortoise Capital Advisors, where he was a managing director and portfolio manager for fixed income and private credit strategies focused on socially responsible investments. Before joining Tortoise, Vesta was an executive director and portfolio manager at Palmer Square Capital Management, where he led the firm's strategies in mortgage-backed securities (MBS) as well as consumer and commercial asset backed securities (ABS). Prior to joining Palmer Square, Vesta was a portfolio manager at Semper Capital Management where he managed multiple strategies involving Non-Agency RMBS, CMBS and ABS, and derivatives. The strategies included registered mutual funds, a mortgage REIT, and a securitized debt hedge fund. Earlier in his career, Vesta worked as an analyst at Earnest Partners where he was responsible for trading and overseeing the firm's MBS positions and also developed proprietary prepayment models for asset backed securities issued by the Small Business Administration (SBA). Vesta is a member of the CFA Institute, the CFA Society of New York, and the CAIA Association.

Education: B.S.; Massachusetts Institute of Technology (MIT)

Tenure with William Blair: Since 2021

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Kathleen Lynch, CFA

Portfolio manager for William Blair's Low Duration Fixed Income strategy. Before that, Kathy was a tax-exempt trader and portfolio manager. She was the lead portfolio manager for the William Blair Ready Reserves Fund from December 2008 through November 2015, and also served as the credit analyst for the William Blair Ready Reserves Fund. Before joining William Blair in 1999, Kathy was a middle-market fixed-income associate at Citigroup, where she was responsible for facilitating trades in taxable and tax-exempt fixed-income securities. Kathy is a member of the CFA Institute and the CFA Society Chicago.

Education: B.S., Business Administration, University of Dayton

Tenure with William Blair: Since 1999

On December 13, 2021, the Fund’s name changed to Ultra-Short Duration Bond Fund.