[squid-users] Does Squid cache "response headers" ?

Hi
One of our user inform me about some problems in viewing one site that
he does not get fresh objects from site's server while site is updated
everyday!!
After some investigate and dig on headers I get, I found out in
response headers that "date" field is for 2 or 3 last week!!
1- Does Squid cache "response headers" ?If so, when user send
"If-none-match" or "if-modified-since" in request header the cached
"response header" will be updated?

Thanks in advance

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N.Chavoshi