Gmail has supported this for a long time with the '+' character, but this has some major problems. Many things that accept email addresses don't recognize '+' as a valid email username character and won't let you submit the form. I hypothesize that some of this is poor awareness of what constitutes a valid email address, and some of it is intentional to force users to input their "real" email address. I have also run across a few systems that stripped off the '+' suffix off my gmail address.

My solution is to use the '.' as the separator because 'firstname.lastname' is a VERY common email username and I'm happy to not allow it in a "real" username on my tiny mail host.

So every new site or company I interact with gets user.acme@example.com instead of my "real" email address. I can filter incoming emails based on the To header. And I even have a list of companies (a couple well-known) that have leaked or sold my email address to spammers. Some day I'll write a blog post about that.

Every entity gets it's own email address. As others have pointed out, it lets me track who ends up with it. Sometimes I find it surprising, mostly I don't. Sometimes, though, people are up to some shit.

edit to say that those actually creating mailboxes for everything should just use aliases that funnel to a single mailbox. So much easier to maintain than having to have a huge keepass db.

edit 2 employ dmarc if you want to see who is trying really game

Gmail is really good at filtering spam, so I probably looked into it and found a letter that I waited for only one time in last few years. My inboxes are either empty or may get first non-spam marketing emails that I unsubscribe from immediately. Unread count zero.

Idk why people fortify their email that much and investigate who does what. Have no issues nor hesitation with leaving my work email at any local org.

I use a catch-all. I can accept (whatever)@mydomain.tld

Anytime a new company wants my email address, I just randomly give them one.

So far I only get spam to the email addresses other people posted on a website as contacts for organizations I volunteer with.

(I get spam from web scraping, not from company hacks/sharing etc.)

Most people who work in the 'email marketing' space know about this feature. So it's common to see people recommending clients to 'clear' their email list before sending unsolicited emails. And some services even offer this as a feature in the platform.

And that also goes for custom domains hosted on gmail. You only need a MX query to learn who is responsible for mail handling in a specific domain.

Of course if unknown@spammer.net write to my amazon-cx1@mypersonaldomain.tld I could try to locate who have sold/leaked my address but it's still vague, since Amazon, eBay, PayPal, have a gazillion of third party. If it's to JoeIKnowNothingAboutIT@maypersonaldomain.tld it's likely he was cracked and so on.

I found that despite what people think, your e-mail address isn't being sold. At least, not by any vendors with a remotely decent reputation. I never got spam to any of those e-mail addresses.

I've seen it as fast as 24 hours my unique email address is being used by others even though their privacy policy says that they will never share your info.

Beyond that I don’t worry about this too much.

As a side note - amazed that iPhone autocorrect corrected my “owned” to pwned in above

I have no idea if this works the way I expect it logically could or should, but if it does I guess I have some data to go thru.

My message stats: You have 245 spamgourmet address(es). 827 emails forwarded, 28,605 eaten.

The #1 worst offender for selling my address was Yahoo, followed by the German magazine Der Spiegel, then Groupon. But my stats go back 20 years, so this may not represent current sharing activity. I also have many many examples of registering at all kinds of sketchy websites that have never used that temp address beyond the initial registration confirmation..

Sorting by created date, in the most recent 5 years, my temp addresses seem to be getting shared and re-used considerably less frequently, which probably correlates to the overall death of email, which is for old people, so I am told.

Addresses which have been lost/stolen and start receiving spam become spam traps, and I change the email address with the company/service to a new alias so their legitimate mail is delivered normally.

In some of the few cases where the loss/theft was identified, it didn't happen at company/service directly, but with one of their suppliers, for example, a breach at the marketing email provider they used.

For instance, if you look at the article he wrote about CBBS[1], you'll see he's listed at apartment #3D.

I never took up the practice, though I suppose I could having the warot.com domain to play with, and a single family residence to make up PO boxes, apartments, etc.

[1] https://vintagecomputer.net/cisc367/byte%20nov%201978%20comp...

Then, if I receive some spam messages, I can delete an alias that I don't want, in order to avoid receiving any messages.

(When someone sends to an invalid alias, the SMTP server gives them a 550 error.)

(I use Heirloom-mailx for reading, managing, and sending email messages.)

I can’t imagine spending more time on this, though.

It's also interesting that some services don't allow COMPANYNAME@mydomain.com for registration. (Can't remember which)

If I find out someone sold/shared/leaked my email what am I going to do?

Here the possible responses as I see it:

* Stop doing business with them - This is way easier said than done

* Be mad - ok, great, now what?

* Send a strongly worded email - again, so what?

* Sue them? - Good luck

Selling or sharing my email address is a shitty thing to do, but my recourse is extremely limited and really ends up with me just being angry with nothing to do about it. Given that I’ve decided just to not care.

There are many things in life that I once cared about or once got worked up about that I don’t anymore because I’ve realized that it’s just not worth it. I’ve tried to identify more and more the things that get me mad, but don’t affect any change and then purge those things from my life. Life is too short to spend your time worrying about things like who sells your email.