Shareholders are going to get to find out about what it feels like to move back toward book value in shares of Zynga Inc. (NASDAQ: ZNGA). The company is very dependent on Facebook Inc. (NASDAQ: FB) for revenues, but a new amended agreement is going to change that. The company showed in a filing that more distance and flexibility will be the new future as the companies lighten up on their interdependence and exclusivity in ads and credits. Facebook also will not have exclusivity on new game launches.

Today’s news should be of little surprise. The writing was on the wall. Zynga needs to show that it can live without such a Facebook step-brother relationship. And Facebook’s payments to Zynga already have fallen by about one-fifth. One concern is that Facebook may now develop its own social games, although this remains to be seen.

This is one of those bits of news that is long overdue, even if it does come with some pain. Zynga shares are down 9% at $2.38 this morning. Its most recent balance sheet showed that its cash plus short-term and long-term investments came to $1.67 billion before factoring in any extraordinary payments or buyouts, versus what is an adjusted market cap of $1.86 billion if you factor in the 9% drop. Zynga has traded in a 52-week range of $2.09 to $15.91.

JON C. OGG