(Telecompaper) Spanish infrastructure company Abertis has announced its intention to sell up to 61 percent of Cellnex Telecom, its recently rebranded telecoms subsidiary, to institutional investors only. In a statement to Spain's market regulator CNMV, Abertis said it expected to sell an initial 55 percent stake in Cellnex, with a greenshoe option increasing that figure to a potential maximum of 61 percent. The company added that the spin off of its mobile unit was one of the key features of its 2015-2017 strategic plan and that the IPO would allow it to accelerate future growth plans in Spain and abroad. Cellnex reported revenues of EUR 436 million in 2014 and recently announced the closure of its EUR 693 million acquisition of Galata, the mobile tower unit of Italian operator Wind. The purchase converted Cellnex into the largest independent European operator of mobile telephone and audiovisual broadcasting infrastructures, with a portfolio of over 15,000 sites, half in Italy and half in Spain.