NEW YORK (TheStreet) -- Shares of Fortinet (FTNT) - Get Report were up in pre-market trading Tuesday despite denying takeover rumors that pushed the stock up more than 23% Monday.

Fortinet is not holding acquisition talks with

IBM

(IBM) - Get Report

, the network security systems-maker said Monday in response to a report from

Bloomberg News

.

The stock was up 1.25% to $32.38 in pre-market trading Tuesday.

Oracle

(ORCL) - Get Report

has acquired e-commerce software company

Art Technology Group

( ATG) for about $1 billion, the company announced Tuesday. ATG's e-commerce platform is highly complementary to Oracle's customer relationship management, retail and supply chain applications, the company said in a statement.

Shares of Oracle rose 0.24% to $29.20 in pre-market trading Tuesday.

IAC

(IACI)

-owned online business directory

Citisearch

announced Monday it was laying off most of its editorial staff and shifting to a freelance system. Citisearch competes with sites like

Yelp

to provide reviews and recommendations of local businesses.

Shares of IAC were up 0.05% in after-hours trading Monday to $27.77.

News Corp

(NWSA) - Get Report

announced Monday that it will acquire a minority stake in Los Angeles-based online advertising company

The Rubicon Project

in exchange for its online ad group Fox Audience Network.

Rubicon Project also said separately that it had raised $18 million in a new funding round, bringing its total funding to $60 million. The company said it will generate more than $100 million in revenue this year, excluding the Fox Audience Network acquisition.

Shares of News Corp closed at $14.51 Monday.

Social news aggregator

Reddit

announced Monday that its top exec,Christopher Slowe, is leaving the company. Slowe will be joining Reddit co-founders Steve Huffman and Alexis Ohanian at their new airiline flight search startup,

Hipmunk

. Reddit was purchased by

Conde Nast

in 2006.

--Written by Olivia Oran in New York.

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