Securitization shelves established by Wall Street investment banks dominated the subprime MBS market during the first half of the year, as major loan originators continued to look for ways to mix their secutization strategies and maximize their execution. Overall, a combined $108.95 billion in new bonds backed by subprime loans were issued off of so-called dealer shelves through the end of June, a total equal to 46.7 percent of the period’s $231.96 billion in… [One data table included]