Check out the companies making headlines before the bell:

Celgene agreed to sell the rights to its Otezla psoriasis drug to Amgen for $13.4 billion in cash. Bristol-Myers Squibb had previously agreed to the Otezla divestiture to win approval for its pending merger with Celgene.

Tesla is planning to raise prices in China this week according to a Reuters report. That would be earlier than originally planned. The electric automaker is said to be considering another increase in December if Chinese tariffs on U.S.-made cars take effect.

Walt Disney will launch stores inside 25 Target locations in October, and plans to launch 40 more of the "stores within a store" by October 2020. The first locations will be in major cities including Philadelphia, Denver, and Chicago.

Drugmaker Mallinckrodt is under scrutiny for its role in the opioid crisis, according to a Wall Street Journal report. The paper notes that the bulk of the attention surrounding opioids has focused on OxyContin maker Purdue Pharma, but that other drug makers like Mallinckrodt are drawing more focus as more legal documents become public.

Defense contractor Raytheon won a $534 million Army contract for infrared viewers used by military tanks to select targets.

3M shares are not at bargain levels despite a 16% year-to-date drop in the shares, according to an article in Barron's. The paper said potential environmental liabilities threaten to erode 3M's valuation further.

Cree was downgraded to "underweight" from "neutral" at Piper Jaffray, following the lighting products maker's last quarterly results and weaker than expected outlook. The firm also cut its price target for the stock to $38 per share from $57.

Dish Network was upgraded to "strong buy" from "market perform" at Raymond James, which sees upside for the satellite TV operator on multiple fronts involving both its pay-TV and wireless operations.

PDC Energy is combining with fellow energy producer SRC Energy in an all-stock transaction valued at about $1.7 billion.

Foot Locker – Susquehanna Financial downgraded the athletic footwear and apparel retailer's stock to "neutral" from "positive", noting disappointing second quarter results and saying that Foot Locker's outlook is still too optimistic.

Lyft – The ride-hailing service's stock was upgraded to "buy" from "neutral" at Guggenheim Securities, citing several factors including rising fares.