When they broke up in 2017, Jennifer returned the ring to David. FYI ... in legalese, an engagement ring is a "gift in contemplation of marriage." If the marriage doesn't go through, in most states the person who gave the ring -- in this case David -- gets it back.
So David has now teamed up with IDoNowIDont.com to unload it. We're told David plans to give a portion of the proceeds to a fathers' rights org.
The ring has a pretty cool history ... the pop singer wore it when she snagged a Grammy in 2009 ... a Grammy presented to her by none other than Whitney Houston. And yes, it's the real deal ... meaning it's GIA certified and comes with official certification docs signed by Lane.