Group 1 - Multiple money market funds have recently announced purchase limits, with minimum limits as low as 10,000 yuan, and some funds have suspended sales through distribution channels [1][2] - The primary reason for these actions is to prevent arbitrage activities that dilute the returns for existing fund holders, despite recent regulatory efforts to standardize practices [1][2] - The average annualized yield for many money market funds has dropped below 1%, prompting fund companies to implement purchase limits to protect investor interests [1][3] Group 2 - The practice of limiting purchases has been observed repeatedly, with funds alternating between imposing and lifting these limits to block arbitrage funds from entering [2][3] - Regulatory bodies have issued guidelines to ensure timely settlement of purchase funds, aiming to enhance transparency and protect investors [3] - Despite the declining yields of money market funds, the total assets in these funds have increased, reaching 15.05 trillion yuan by the end of October, up by over 380 billion yuan since September [4]

Core Viewpoint - The yield of money market funds has been declining throughout the year, with a median annualized yield of 1.24% as of December 16, 2023, leading to many funds implementing purchase restrictions to protect long-term investors from dilution of returns due to arbitrage activities [1][2][4]. Group 1: Yield Trends - As of December 16, 2023, 941 money market funds reported a median seven-day annualized yield of 1.24%, with 102 funds yielding below 1% and over 300 funds yielding between 1% and 1.2% [2]. - The largest fund, Tianhong Yu'ebao, maintained a yield above 1%, specifically at 1.014%, showing a slight recovery from a previous low of 1.001% [2]. Group 2: Fund Management Responses - In response to declining yields and arbitrage pressures, several fund companies have announced purchase restrictions or even halted new subscriptions to protect existing investors [5][6]. - Specific funds, such as the Fuan Da Cash Fund, have implemented measures to suspend subscriptions while allowing transactions through certain channels to maintain operational stability [5]. Group 3: Market Dynamics - The increase in money market fund sizes, which grew by over 380 billion units to 15.05 trillion units by the end of October, contrasts with the declining yields, influenced by lower interest rates on demand deposits and market volatility [3]. - The phenomenon of "deposit migration" has affected banks' liquidity management, increasing friction in fund flows and contributing to yield volatility in the money market [2]. Group 4: Arbitrage Concerns - Fund companies are limiting purchases to prevent arbitrage activities that dilute returns for existing investors, as new investors can benefit from yield accrual during the time funds are held in transit [6][7]. - Regulatory measures have been introduced to tighten the timing of fund subscription settlements, yet loopholes remain, prompting fund companies to adopt purchase limits as a protective strategy [7].