Microsoft CEO Satya Nadella Microsoft

For the first time in many years, Microsoft is not banning any competitors from attending the World Partner Conference (WPC) '15, its biggest event of the year, a Microsoft spokesperson has confirmed.

In years past, VMware, Oracle, Salesforce, and as of last year, Amazon, were all explicitly banned from Microsoft WPC in an effort to protect against the leaking of trade secrets. This ban was first noticed back in 2013, but it may well have been in effect for longer — it's not something Microsoft is especially keen on discussing.

WPC is the annual event where Microsoft gives updates on its latest projects, initiatives, and products, to people and companies who build on top of and support Microsoft technologies. It's intended to keep everybody whose business depends on Microsoft updated on what the tech titan is up to.

It's tempting to take the lifting of the ban as a further sign of real change at Microsoft in the Satya Nadella era. In years past, the company was playing a defensive position, and outright banning competitors from attending could have been interpreted as a signal that it was worried.

Opening the doors to competitors could be a sign that Microsoft is confident and willing to potentially work with these companies.

Microsoft's other events, like Build, which is focused on app developers, have always let competitors in.