Are companies in US sponsoring candidate from abroad to come to US for work? How can I find such companies and how easy is it get visa sponsored jobs in US?
I tried linkedin but almost every company asks for a valid US work visa.
Unfortunately, the number of work visas for US is quite limited. 65,000 a year in H-1B, high-skilled jobs (presumably what you're looking for). The category is over-subscribed every year by a factor of 3. Many employers have decided the odds are not worth it. Your odds are better, and you can work a bit (3 years) post-graduation, if you get an advanced degree in the US. There are also other categories of visas for intra-company transfer and such.
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US tech companies are generally no longer interested in bringing foreigners from abroad on H1B - it's mostly dominated by indian body shops today. Wage levels rule changes might change this status quo but it's not in effect yet. Companies would consider H1B if you're already in the states on this or another type of visa, or working for them already from abroad. In the latter case you have an easier option of L1A/L1B transfer without any lotteries, with the catch that you won't be able to switch employers until you get GC.
A popular alternative is F1 - study for masters/phd in the US. Upon graduation you can stay work for 1-3 years on (STEM) OPT. 3 years is enough time to get proper H1B or green card, unless you were born in India or China.
For exceptional candidates, there's EB1, EB2-NIW - you can self-sponsor these without a company if you think you fit the requirements. Another type is O-1, company sponsorship required for this type but it could be your own startup and once you're in, you can work for another company on it. Biden reintroduced Entrepreneur Parole recently, another way to get into the states to roll your own startup.
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