This is the reciprocal to this question. Currently, I am trying to use the instant client for Mac, version 10.2. There\'s no 11g version for Mac, as of now, based on this page(y
There can be problems when a lower version client is used to access a higher version database, particularly when using links where you might get some erroneous results.
See Document ID 207303.1 on My Oracle Support for more details (if you have access).