This looks like normal 50% retracements. The post 9-11-01 low last September was 15.85. The January '02 high was 27.84. The February '02 low was 21.94, or 10 cents above a 50% retracement I calculate to be 21.845.
From the February '02 low to the 33.99 recent high, a 50% retracement would be 27.965, so Friday's intraday low was $1.95 below this retracement but the close was only $.765 the retracement. SIVB is still above the 200 day moving average. We'll see Monday if the 200 day holds or not.