Unlike previous years Apple has barred WWDC ticket resale, a move that's sure to irk scalpers, who have made hundreds, sometimes thousands, by turning tickets on eBay and Craigslist.

"WWDC tickets (including activation codes) are non-transferable and may not be sold, resold, or auctioned in any way," the WWDC website said.

Ticket transfers among development team members will be considered on a case-by-case basis, Apple added.

Last year, tickets were shilled on eBay at prices from $2,125 to $4,599 a day after they ran out from Apple. Meanwhile, sellers on Craigslist were asking $800-$900 above face value.

Apple has not posted an agenda for the event, saying only that, "Developers will learn about the future of iOS and OS X, allowing them to build incredible new apps."

It's certain, however, that Apple will hold sessions on Mountain Lion, or OS X 10.8, which Apple has promised to deliver to customers later in the summer.

Also likely to be on the schedule: The next version of iOS, Apple's mobile operating system for the iPhone and iPad.

Apple has said nothing about an upcoming upgrade for iOS, but it regularly announces new editions at WWDC. It used last year's conference to introduce iOS 5, which powered the iPhone 4S when it launched four months later.

This will be the first WWDC for Apple since the death of former CEO Steve Jobs, who lost a years-long battle with pancreatic cancer last October. At the June 2011 event, Jobs, on medical leave at the time, took the stage during the opening-day keynote to introduce OS X 10.7, aka Lion.

If Apple hews to tradition, CEO Tim Cook will lead this year's keynote, which will probably take place on the morning of Monday, June 11 to kick off the conference.