There were five deals reported in the last seven days that tipped over the $5 billion mark, including Thermo Fisher Scientific's $20.9 billion buy of PPD, Kimco Realty Corp.'s $12 billion merger with Weingarten Realty Investors and, on Monday, Webster Financial Corp.'s all-stock merger with Sterling Bancorp, valued at $10.3 billion. Two partners at Simpson Thacher & Bartlett managed to have a hand in a lot of the above, helping to shepherd several 11-figure deals.