William Blair Funds has made a significant update to its Statement of Additional Information (SAI), which is now effective as of November 2, 2026. This filing is crucial for investors as it provides detailed information about the various funds and classes offered by the company, ensuring transparency and compliance with regulatory standards.

The SAI is an essential document for investors, offering insights into the investment strategies, risks, and financial information related to the funds managed by William Blair. This update reflects the company's commitment to maintaining clear communication with its investors and adhering to the guidelines set by the U.S. Securities and Exchange Commission (SEC).

Background

William Blair Funds, based in Chicago, Illinois, operates as an investment management company. The firm focuses on providing a range of mutual funds, including growth funds, value funds, and international funds, catering to various investor needs. The company has undergone several name changes in its history, previously known as William Blair Mutual Funds Inc and Blair William Ready Reserves Inc.

As of November 2, 2026, the company has filed multiple recent documents, including several other 497 forms, indicating ongoing updates and adjustments in its offerings. This consistent communication with the SEC highlights the firm's proactive approach to regulatory compliance.

What the Filing Says

The recent filing outlines the various funds and classes available to investors, including:

  • William Blair Growth Fund (Class N: WBGSX, Class I: BGFIX, Class R6: BGFRX)
  • William Blair International Small Cap Growth Fund (Class N: WISNX, Class I: WISIX, Class R6: WIISX)
  • William Blair Emerging Markets Growth Fund (Class N: WBENX, Class I: WBEIX, Class R6: BIEMX)
  • William Blair Large Cap Growth Fund (Class N: LCGNX, Class I: LCGFX, Class R6: LCGJX)
  • William Blair Small Cap Value Fund (Class N: WBVNX, Class I: ICSCX, Class R6: WBVRX)

These details are crucial for investors looking to understand their options and make informed decisions.

Impact

The update may affect current and potential investors in William Blair Funds, as well as competitors in the investment management industry. By providing clear and updated information, the firm aims to enhance investor confidence and satisfaction. This move could also influence how other firms approach their disclosures and communications with investors.

What's Next

The filing does not specify what happens next, but investors can expect ongoing updates and communications from William Blair Funds as they continue to adapt to market conditions and regulatory requirements.

For more information, investors can access the filing through the SEC's website, referencing accession number 0001193125-26-442779.