( Star Scientific item was corrected to reflect it is not a secondary offering. Please see the correction here..) NEW YORK ( TheStreet) -- Star Scientific ( CIGX) registered 18.05 million shares by selling shareholders under a prospectus. Star Scientific closed Monday at $1.88 and slumped more than 4% in the after-market session after a regulatory filing showed that stockholders could sell up to 18.05 million common shares. Star Scientific said it is not selling any common stock and will not receive any of the proceeds from the sale. Star Scientific shares have fallen hard since the company announced a collaboration with Roskamp Institute on Beta-amyloid discovery to treat Alzheimer's disease, falling more than 32% since April 8. The 50-day average daily volume for Star Scientific is 4.65 million, according to the Nasdaq. Elsewhere, Array BioPharma ( ARRY) jumped by 78 cents, or 25.8%, to $3.80 in the premarket session after the company said it has entered into a $467 million licensing agreement with Novartis ( NVS) for the development of the cancer drug candidates ARRY-162, ARRY-300 and other small-molecule MEK inhibitors. Array will initially receive $45 million comprising an upfront and milestone payment and is eligible to receive an additional $422 million if certain clinical, regulatory and commercial milestones are achieved. Array is eligible to receive double-digit royalties on sales of the approved products outside the U.S., and it becomes eligible for a "significantly higher" royalty rate on sales in the U.S. if the company meets co-funding obligations. The 50-day average daily volume for Array BioPharma is 303,000. FalconStor Software ( FALC) dropped by 36 cents, or 11%, to $2.90 in the premarket session after the company offered preliminary results for the first quarter, saying it expects a loss of 8 cents to 9 cents a share on revenue of $16.8 million to $17.1 million. Analysts are looking for a loss of 2 cents a share on revenue of $19.4 million, according to Thomson Reuters. FalconStor said the revenue shortfall is due to lower-than-expected software license revenue, particularly international software sales. The 50-day average daily volume for FalconStor is 160,000. Ambac Financial ( ABK) continued to bounce from its recent pullback, rising by 18 cents, or 9.3%, to $2.12 in the premarket session after shares rose 10.2% during Monday's session. Ambac rallied on the bond insurer's better-than-expected fourth-quarter results over a week ago, before pulling back on a JPMorgan analyst's comment that the equity is "worthless." The three-month average daily volume for Ambac is 41.58 million, according to Yahoo! Finance. -- Written by Robert Holmes in Boston. Check out all of Tuesday's high-volume, under-$5 stocks at the Dollar Store. View the Dollar Store portfolio on StockPickr. Follow Robert Holmes on Twitter and become a fan of TheStreet.com on Facebook.