And since DH was recruited directly by a UK company, I assume his visa will be straight Tier 2, but I will check on that!
ICT stands for Intra-Company Transfer. If he hasn't just transferred to the UK from his US office, then he won't be on the temporary Tier 2 (ICT) visa. The visa should say Tier 2 (General) visa. The UK limits the Tier 2 (General) visas to just 20,700 a year from outside the UK and the employers know if they will be able to get one of these when they make the offer.
The latter (Tier 2 ICT) does NOT to permanent residence and you'll have to leave the UK at the end of it.
They only have to leave at the end of their temporary transfer to the UK office on their ICT visa, if they or their dependant spouse do not have the skills the UK needs. These Tier 2 (ICT) visa holders have a 12 month cooling off period outside the UK before they are allowed to return to the UK on another work visa. This prevents them and any dependants from getting settlement (Indefinite Leave to Remain) in the UK under the 10 years of lawful stay for ILR.
If the Tier 2 (ICT) visa holder can find a new employer who will pay them at least £159,600, they can have a Tier 2 (General) visa and these are not required to have the 12 months cooling off period outside the UK.
The Tier 2 (ICT) visa holder can switch (in country) to the Innovator visa; the Start-up visa; Exceptional Talent visa (Tier 1); Investor visa (Tier 1); no 12 month cooling off period required outside the UK for these either.
If the Tier 2 (ICT) visa holder's dependant spouse has the skills to get one of the 20,700 Tier 2 (General) visas, the ICT visa holder switches to being their dependant. There is no 12 month cooling off period outside the UK for those who are the dependant.