Merger Monday is back with a vengeance, with more than $72 billion worth of deals announced in the telecom, energy, retail and real estate sectors.

Bigger picture: Global M&A activity is up 56% from this time last year while U.S. M&A is up 29%, per Thomson Reuters.

• T-Mobile and Sprint yesterday agreed to a $26 billion tie-up, which would create America's second-largest wireless carrier (leapfrogging Verizon, still behind AT&T).
• Marathon Petroleum agreed to buy Andeavor for $23.3 billion, which would create the largest U.S. oil refiner by capacity (overtaking Valero Energy).
• Marriott Vacations Worldwide agreed to buy ILG for $4.7 billion, which Bloomberg says creates "the largest luxury brand for timeshare vacation resorts."
• Prologis agreed to acquire DCT Industrial Trust for $8.4 billion in stock, putting even more distance between Prologis and lesser rivals in the global warehouse and distribution center market (a market that's surging in the world of Amazon and broader e-commerce).
• Sainsbury's agreed to merge with Walmart's Asda in a $10 billion tie-up that would create Britain's largest supermarket operator.