How long can we wait to file I-485 after approval of I-140?

If My I-140 is approved and my priority date is eligible to file I-485, but I decide to postpone the filing of I-485, How long can I postpone it? Is there a requirement that we should file I-485 in a certain period after the approval of I-140?
Thanks.

所有跟帖： 

• 回复：没有严格规定，一般半年左右就认为你自动放弃 -radiology- ♂ (0 bytes) () 08/31/2007 postreply 10:15:07

• 回复：回复：没有严格规定，一般半年左右就认为你自动放弃 -Question100- ♂ (58 bytes) () 08/31/2007 postreply 12:00:14

• 为何要postpone呢？申请140不就是为了进一步申请485吗？ -小燕南南飞- ♀ (94 bytes) () 08/31/2007 postreply 11:13:44

• 回复：为何要postpone呢？申请140不就是为了进一步申请485吗？ -cocoine- ♀ (68 bytes) () 08/31/2007 postreply 11:14:58