Company: MYI
Filing Date: 2025-07-15
Form Type: 425
Source: 0001193125-25-159406
Chunk: 4

Company: BLACKROCK MUNIYIELD QUALITY FUND III, INC.
Filing Date: 2025-07-15
Form: 425
Chunk 4
---
 Fund and the Investment Advisor have entered into a waiver to the Standstill Agreement (the “Waiver”) with Karpus, pursuant to    
 which each of the Fund, the Investment Advisor and Karpus have agreed to waive the Fund’s obligation under the Standstill Agreement to commence a Conditional Tender Offer as soon as practicable following the end of the calendar quarter ending 
 September 30, 2025 (the “Sixth Measurement Period”) if the Fund’s Shares trade at an average daily discount to NAV greater than 7.5% for the Sixth Measurement Period. A copy of each of the Standstill Agreement and the Waiver is                
 included as an exhibit to the Fund’s Schedule TO for this Offer. This Offer to Purchase and the Letter of Transmittal relate solely to the Offer and do not relate to any other Conditional Tender Offers.                                         |

i

| • |     | There can be no assurances as to the effect that the Program will have on the Fund’s market discounts.                                                                                                                                          
 Common shares of closed-end investment companies often trade at a discount to their NAVs, and the Fund’s Shares may also trade at a discount to their NAV, although it is possible that they may trade at                                       
 NAV or at a premium above NAV. The market price of the Fund’s Shares is determined by such factors as relative demand for and supply of such securities in the market, the Fund’s NAV, general market and economic conditions and other factors 
 beyond the control of the Fund. Therefore, the Fund cannot predict whether its Shares will trade at, below or above NAV. (See Section 2, “Purpose of the Offer” and Section 3, “Plans or Proposals of the Fund.”)                               |

Will I have to pay anything to participate in the Offer?

| • |     | Shares will be purchased at 98% of the Fund’s NAV, which may help defray certain costs of the offer,                                                                                                                                                   
 including the processing of tender forms, effecting payment, postage and handling. The Fund will not charge a separate service fee in conjunction with the Offer. If your Shares are held through a financial intermediary, the financial intermediary 
 may charge a service fee for participation in the Offer. (See Section 1, “Price; Number of Shares,” Section 7, “Payment for Shares” and Section 17, “Fees and Expenses.”)                                                                              |

What is the NAV per Share as of a recent date?

| • |     | On July 8, 2025, the NAV