Approximately two years after it was spun off by R.R. Donnelley as a standalone printing and manufacturing company, LSC Communications has agreed to be acquired by Quad/Graphics in an all-stock deal valued at $1.4 billion acquisition is expected to close in mid 2019.

The purchase will unite the country’s two largest printers—Quad had sales in 2017 of $4.1 billion, while LSC had sales of $3.6 billion. LSC reported book printing revenue of $1.1 billion in 2017, up from $925 million in 2016. Quad does not break out its book printing sales.

The deal also continues the rapid consolidation in the printing industry that has occurred in recent years. Indeed, both companies grew to their current size through a host of purchases, among them LSC’s (then known as Donnelley) purchase of Courier Corp. Donnelley bought Courier after Quad had made an earlier offer for the company.

“This is a defining moment in Quad’s 47-year journey,” said Joel Quadracci, Quad/Graphics chairman, president and CEO, in a statement. “We have grown from a printer with a single facility to a global marketing solutions provider with a seamless, integrated offering that creates more value for all our stakeholders at a time of significant media disruption. Together with LSC Communications, we will create a compelling combination of talent, expertise and client technology” which will “strengthen the role of print—a proven and trusted media form in today’s multichannel world.”

The consolidation in the printing industry, which has featured both mergers and closures (most notably the closing of Edwards Brothers Malloy), has publishers concerned about the ability of printers to meet demand during the holiday season.