The companies whose shares are moving in pre-market trade Monday are: Demand Media, Barnes & Noble, Sunoco, Mannkind Corp, Boston Scientific Corp, Vivus Inc, Range Resources Corp and Humana Inc.

Demand Media Inc. (DMD) stock climbed 48.97 percent to $10.80 in pre-market session. The company has turned down $1.2 billion dollars in a deal, which would have taken the company private last week, due to a number of challenges, including complications related to its financing and the ability to retain executives in its aftermath, AllThingsD reported.

Barnes & Noble Inc. (BKS) stock climbed 79.09 percent to $24.50 in pre-market trading. Microsoft & BKS announced the formation of a strategic partnership in a new Barnes & Noble subsidiary. Microsoft will make a $300-million investment in new company at a post-money valuation of $1.7 billion in exchange for an approximately 17.6% equity stake.

Sunoco Inc. (SUN) stock climbed 22.12 percent to $49.96 in pre-market session. Energy Transfer Partners, L.P. announced that it has agreed to buy Sunoco for $5.3 billion in stock and cash to strengthening its presence in the transportation, terminalling and logistics of crude oil, NGLs and refined products.

Mannkind Corp. (MNKD) stock climbed 12.50 percent to $2.52 in pre-market session. Tolero Pharmaceuticals and MannKind announced a license agreement granting Tolero exclusive worldwide rights to develop and commercialize compounds from MannKind's novel BTK (Bruton's tyrosine kinase) program, which are currently being developed for the treatment of hematological malignancies and inflammatory diseases.

Boston Scientific Corp. (BSX) stock surged 8.93 percent to $ 6.83 in pre-market session. The stock has a 52-week low of $5.01, a 52-week high of $7.91 and $8.99 billion in market capitalization.

Vivus Inc. (VVUS) stock gained 3.38 percent to $26.00 in pre-market session. The stock has a 52-week low of $6.13, a 52-week high of $26.75 and $2.24 billion in market capitalization.

Range Resources Corp. (RRC) stock gained 2.25 percent to $65.35 in pre-market session. Analysts at Canaccord Genuity reiterated their hold rating on shares of Range Resources.

Humana Inc. (HUM) stock declined 3.21 percent to $85.00 in pre-market session. The company reported first quarter net income of $248 million or $1.49 per share, down from $315 million or $1.86 per share in the same period last year and also fell short of analysts' estimation of $1.53 per share.