The Planning Inspectorate has given its recommendations to secretary of state for energy and climate change Ed Davey. He now has three-months to make a ruling on whether the development should go ahead.
The recommendations are complex summing up of the case for and against the development, taking into account input from interested parties, rather than an instruction to approve or dismiss plans.
Walney 1 and 2, with a combined capacity of 367MW, are already operating near the site of the planned extension and were developed by Dong and SSE.
The up-to-750MW third phase is being developed solely by Dong, 19 kilometres from the English west coast. Construction is slated to start at the end of the year, with commissioning expected in 2016.
It will be made up of up to 125 Siemens 6MW turbines, installed on jacket and monopile foundations.