When students register for the SAT, they can send their SAT scores to four schools for free. Later on they can pay to have their SAT scores sent to more schools. After reading this article, I conjectured that some schools that are sent SAT scores early may interpret this as a sign of applicant interest. Reading the College Board site http://sat.collegeboard.org/register/sat-score-choice confirms this:

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Should I send my scores early?
If you know which schools you'd like to send your scores to and are comfortable sending your scores in the spring of your junior year, you should do so. Some colleges see this as a sign of interest. They may also use scores to qualify you for special campus visit programs, information sessions in your hometown or scholarships.

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