* Thermo Fisher in $13.6 bln Life Tech takeover
* Dish Network bids for Sprint Nextel
* U.S. CEOs pursue large deals for growth, cost cuts
* Barclays No. 3 global M&A adviser, JPMorgan tops league table
The more than $52 billion worth of deals announced on Monday morning made it the busiest "merger Monday" this year, as two large U.S. corporate takeovers underscored increasing CEO interest in pursuing transformational transactions to boost growth and cut costs.
Dish Network Corp, the No. 2 U.S. satellite television provider, made a $25.5 billion bid for Sprint Nextel Corp, challenging the proposed acquisition of Sprint by Japan's SoftBank Corp, while Thermo Fisher Scientific Inc struck a $13.6 billion deal to buy Life Technologies Corp.
Meanwhile, U.S. investment firm Royalty Pharma sweetened its bid for Irish drugmaker Elan Corp Plc to as much as $7.3 billion, formalizing its initial approach.
The day's slew of announced transactions brought the value of global mergers and acquisitions so far this year to $650.2 billion, up 14.5 percent from $568.1 billion during the same period in 2012, according to Thomson Reuters data.
U.S. companies accounted for more than half of that activity, with $331 billion worth of deals through April 15, up from the 32 percent share in the same period last year, when deal volumes in the country totaled $181.9 billion.
"If you're a well-capitalized company, one that has cash and access to capital, and if you have strategic imperatives, now is going to be looked at as a very compelling time to acquire," said Paul Parker, head of global corporate finance and M&A at Barclays.
"Volatility has come down meaningfully, interest rates are low, corporate cash levels are high and dilutive just sitting unproductively on balance sheets, and there is pent-up strategic demand. This is why we are seeing industry and company transforming deals."
The first four months of the year already saw several large corporate deals, including the $23.2 billion takeover of ketchup maker H.J. Heinz Co by Warren Buffett's Berkshire Hathaway Inc and Brazilian private equity firm 3G Capital.
Other large deals include the $24.4 billion bid to take Dell Inc private by founder Michael Dell and buyout firm Silver Lake Partners, as well as the merger of US Airways Group Inc and AMR Corp, the bankrupt parent of American Airlines.
"There is increasing confidence in the United States as a safe haven and as a stable place to invest," Parker said.
"CEOs here have more visibility to their own companies' futures as well as the futures of the targets they're looking at in this market," he said, adding that the political and economic uncertainties in Europe and Asia continue to be an overhang.
European deal activity is down 23 percent to $138.4 billion, while Asia-Pacific saw a 10 percent decline in deal volumes to $91.4 billion, Thomson Reuters data shows.
Barclays, which was involved in two big deals announced on Monday, rose to No. 3 in the global ranking of M&A advisers, up from eighth place as of last Friday.
The bank was the sole adviser to Dish on its $25.5 billion offer for Sprint, and advised Thermo Fisher along with JPMorgan Chase & Co on its acquisition of Life Technologies.
JPMorgan, with its role in advising Thermo, rose to No. 1 in the league table, ahead of Goldman Sachs Group. Deutsche Bank and Moelis advised Life Technologies on the deal.
Mondays are often active days for merger news because companies tend to finalize terms of a deal over the weekend and then roll out the announcement before the market opens on Monday.