Sprint will lease its interests in rooftop transmitters and other sites to the JV, says a Lendlease spokesman; the WSJ originally had reported that the assets would be sold to the venture. Over time, the JV will focus on partnering with major US carriers to roll out further phases of their infrastructure expansion plans.

In a presentation to investors last month, Denis Hickey, Americas CEO for Lendlease, spelled out the rationale for the JV as far as his company was concerned. “We see an opportunity for Lendlease to play more of a development solution in the broader sector, not just with the Sprint and Softbank business, but also with other carriers in the US,” Hickey said in September. “When you look at the dynamics that are happening in the telco business and the amount of data usage that's happening as we move forward,” driven by the rollout of 5G, driverless cars and the Internet of Things, “the quantum of data that's going to be transmitted is growing exponentially.”

Hickey told investors that Lendlease is developing 423 new rooftop towers in the US, with 135 already completed. The development pipeline came courtesy of Lendlease's acquisition of Parallel Infrastructure from Florida East Coast Industries this past May. Additionally, while the industry standard generally has two carriers at a time leasing a tower, Lendlease plans to bring in multiple tenants over time.

“Lendlease has group scale and an integrated platform, with strong relationships with the major carriers,” he said last month. “The strategic intention is to co-invest in a long-term ownership vehicle.”

Hickey's presentation also charted the rapid growth of telecom towers in the US as data usage has increased exponentially. Between 2000 and 2005, the needle didn't move dramatically above the 50,000-tower mark, but over the next five years the count ballooned to about 125,000. It's projected to exceed 200,000 by the year 2025.

At present, the US market is dominated by its three largest operators, as Hickey's presentation made clear. American Tower and Crown Castle International Corp. each operate about 40,000 cell towers domestically, while the SBA Communications Corp. portfolio runs to about 16,000. Among them, the three REITs account for approximately 75% of the current tower count in the US.