Meta Expires Tag Example:
The following is an example of how you can use the Meta Expires tag:
Note: Time zone must be stated in Greenwich Mean Time (GMT) not EST, PST or any other.
Use the following tag to expire content immediately:
The above tag is also said to disable caching so that search engines will load a new copy of the site from the server every time an end user visits the site.
Meta Expires Recommendations:
It is recommended that you do not use the Meta Expires tag. If you are looking for a way to stop Google from caching your site, the Meta Expires tag will not do this for you. While the concept is good, it is impractical for the search engines to follow. Google will still cache your web page even if you have chosen to use the Meta Expires tag. According to my testing, both search engines and browsers will ignore the Meta Expires tag completely, just like you should do. This tag is worthless and needs to be deleted from use.
If you would like Google to stop caching your web page, use the following code:
Note: The above tag belongs with your other Meta tags that you have entered at the top of your web page as well.
Read more: http://www.webmarketingnow.com/tips/meta-tags-meta-expires.html#ixzz3gcqRgKVH