<p>From the Yale site (It took me longer to cut and paste than to find):</p>
<p>Which standardized tests does Yale require?
Yale requires either the SAT I or the ACT. Students who submit scores for the SAT I are also required to take two of the SAT II Subject Tests. They may take any two subject tests of their choosing. The middle 50 percent of Yale’s entering class this year had scores between 700 and 790 on both the verbal and the math sections of the SAT I.</p>
<p>in other words: For SAT I you must have 2 subject tests, for ACT they are not required.</p>