Old Domains - What to do

[Blue_Vision]

I've got a bunch of old domains (say they are all about 3 yrs old) to sites I'm either going to shut down as I've kinda abandoned them anyways or already shut down and had the domains pointed at the sites I'm going to shut down (sorry, kind of a tongue twister).

Here is a visual incase it helps. These are bogus made up domains I'm just using as an example:

genericshirtcompany.com (old site, going to shut down now)

sacramentoshirtcompany.com (shut down long ago, domain now forwards to genericshirtcompany.com above)
losangelespants.com (shut down long ago, domain now forwards to genericshirtcompany.com above)
bluesweaters.com (shut down long ago, domain now forwards to genericshirtcompany.com above)

shirtcompany.com (my main master site now)

I'm doing web house cleaning since we are moving our stuff to a new server and I'm trying to simplify and avoid continuing to pay for domains that might be useless for SEO and I'll never use them again for a site.

Is there a potential noticeable benefit in terms of SEO to point all the domains I have which are relevant in name and about 3 years old each.... to point/forward them all at my master domain now? Or is that a waste of money and complicating things up for little or no benefit?

Thanks for the advice

[Blue_Vision]

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