I work remotely from my home country for a US-based company. Definitely that company is not registered in my home country.
Now, my employer wants to meet with me in person. What would be best explanation for this situation if I am applying for a B-1 visa?
State (supposing it is true) that the purpose of your visit is to have meetings to plan and coordinate ongoing work you're performing for the employer in your home country.
This is a permissible activity for a business visitor, whereas actually doing the work would not be. So be sure not to give the impression that you'll be doing "productive labor" during your visit.
At least this would unambiguously be the case if you were employed by a foreign subsidiary of the US company. If the US company is paying you directly, things are unfortunately a bit less certain, because some statements of the test for "business visitor" require that the alien's salary must come from abroad. On the other hand, other statements say that this is satisfied if you're paid after you return home. In any case, your best bet is to tell it like it is in the visa application. If they don't allow you in, you want to find that out at the visa application stage rather than when you reach the border at a US airport.
(As one anecdotal data point, when I have arrived at the border and declared my intent to be "one week of meetings at my employer's [city] office", I haven't been asked to explain legal arrangements between me and said employer. On the other hand, I'm a white VWP traveler, and it is possible that visa nationals are given greater scrutiny, even though the formal requirements are the same between the VWP and B-1/2).
As stated in other answers, it's important to say that you're visiting for meetings and not to carry out any actual work.
From personal experience, as a contractor who travels frequently to the US to meet with clients, I was once given a very tough grilling by a US immigration officer who asked me the details of my contractual arrangement, whether my own company (through which I contract) had any employees in the US, whether I'd be doing any paid work, how I came to be working for these clients, how I got paid by them, etc. He asked to see my business card to verify I was indeed an independent contractor and not an employee of a US company.
Be prepared to answer lots of very detailed questions about your relationship with this company, how and where you work for them, and how they pay you.
Never use the term employer (unless you really are a salaried employee)
State that you are visiting a client of your consulting business.
update (because of negative comments) It is highly unlikely you actually have an employer-employee relationship in the same terms as viewed by the IRS. However, especially for people for whom English is not their primary language, it is common to refer to my boss or my employer in conversation.
In the formal context of answering visas, use the simplest and least-likely-to-be-misinterpreted answer.
Similarly when talking to immigration officials - be very careful of your precise words because they have some trigger phrases.
You do not have to have a formal local corporation to be an independent business with a client in the USA. Different jurisdictions have entirely different legal interpretations - be very aware of yours and any areas which are loosely defined.
I have worked remotely for many US clients. At different times I have had different local Australian corporate structures. I have often only ever had the one regular client with a person I regarded as my boss but was always clear that they are legally not an employer.
Good luck getting things organised before the next US government shutdown!
