Fitch Ratings published "Money Market Tranches in Structured Finance" on Monday. The report says, "Money market (MM) tranches issued as part of global structured finance transactions constitute eligible securities for purchase by money market funds under Rule 2a-7 of the U.S. Investment Company Act. Due to their short-term nature -- final legal maturity cannot be more than 397 days after closing -- Fitch Ratings assigns Tier 1 short-term ratings ('F1+' or 'F1') to these securities at issuance. The market for MM tranches is sizable and continues to grow; Fitch notes that the investor base is also expanding, as corporate treasurers and short-term fund managers, among others, continue to look for cash alternatives." The study's "Key Findings" include: "Issuance of structured finance MM tranches has recovered from crisis-era lows. The number of Fitch-rated MM tranches reached new highs in 2011 and 2012, largely driven by U.S. ABS.... U.S. ABS MM tranches continued to be successfully issued in 2008 and 2009, while many other sectors remained in virtual standstill. The sector represents one-half of the outstanding Fitch-rated MM tranches and continues to account for the majority of new ratings.... MM tranches can be divided into two main categories: those where the term of assets and liabilities is matched (e.g., ABS) and those where long-term assets are funded with short-term liabilities (e.g., RMBS). The first category accounts for 84% of Fitch-rated tranches and is the typical structure for U.S.-issued MM tranches."