For others it's too costly and not necessary.
I have heard that some country's ext.s are hard and expensive to register, but the top 5 ext.s are 10 bucks a piece. Whats going rate for a lawyer about 150 an hour, I bet one email that a lawer sends costs a company 50 bucks...
I would think a company would want to register the names in at tleast the top TLDs, why they don't I have no idea...
Many thousands of companies have been around since not just the 1900s but also the 1800s. But you don't see many thousands of company trademark versus domain name disputes being arbitrated by WIPO. Why? Because most large companies already HAVE registered their names in one or more of the TLDs of .com, .net or .org.
The comparatively few disputes that we DO see are the result of some short-sighted brick and mortar-only companies who thought either that the internet wasn't worth bothering about that much, or at the other extreme they assumed that dot coms automatically came with trademark approvals, anyway - but they DON'T.
It's still first come, first serve. And as long as your site isn't violating the fair use rules, companies can do nothing about you grabbing their name first. Also, although you're not allowed to advertise it for sale or contact them first, THEY can approach you and THEN purchase it. It was their own fault for not being quicker on the trigger a few years back, after all.
(And you have to know that SOMEBODY got fired over that oversight - it's just that since we don't work for those companies, we never get to hear about it!)..
Well when you (or anyone for that matter) register a decent available .com with intentions to develop do you register all extensions possible? I would venture to say no because you feel the .com is king (which it is) and have no need for the rest. You rely on the law protecting you if someone not only registers those extensions but also infringes on your site or business..
I would think many companies don't find it important to grab all extensions. I think they are right. If you have bicpens.com what good is the .net or .org to you?..
Okay, as to the specific "all extensions" reference, some companies (and private individuals), as I indicated, missed the boat with getting the dot com. So they registered the .net, or if that was also taken, the .org. They didn't plan it that way - it's just that Johnny-come-latelys have to take what's left when someone else beats them to it.
(It's also always quite funny to see it whenever a big crude 'n' rude company in New York is powerless because some little guy out in Iowa has a fair use fansite using a name similar to theirs, that they can't pry out of his fingers and don't want to pay him for. Must drive 'em crazy!)..
Why don't companies register all the .exts under their trademark?.
1. Too costly...especially for companies that may have thousands of trademarks..
2. Unnecessary...If the secondary extension gets used in violation of the trademark they can stop it or file for monetary damages. Big companies with .com may see only minor spillover in other TLD's and not worth the cost of maintaining..
3. Short sightedness...Some companies just don't think to do it. Some could not get them when new TLD's came out due to other companies having fair use in another category...
What does all extensions mean? Is it all the gTLDs, the ccTLDs, the 2L ccTLDs? You're talking about hundreds of names here. Then all the typos, hyphens, etc. You're looking at thousands, perhaps tens of thousands, of names. The reg fees alone could easily run to 100k, not to mention the overheads of running the Domain Department that manages them all. And, of course, since many ccTLDs have residency requirements the cost of setting up a corporation in each country. Even if they're not trading.
So you're potentially looking at $1M/year to protect against cybersquatters who you have to deal with a few times a year at a cost of what $10K each? It's not economical.
Most very large companies get the .com, .net, and ccTLD of the countries they do business in. But I think that's mainly because they actually use them...