Get your taxes done using TurboTax

The sailing permit primarily is to ensure you pay your taxes. You can file your return without a problem. 

You may be required to have a sailing permit. I don't see the L1B as exempt. If you plan to return, it may not hurt to contact the IRS and verify there are no issues. There are IRS offices in Frankfurt, London, Paris, and Beijing (if you are in or near one of those countries); if not, I suggest that you call the IRS 267-941-1000 (not a toll-free call) for guidance.

A nonresident alien will file US source income with Sprintax. They may be better able to help with your other questions as well.

Departing alien clearance (Sailing permit) states:

If you are in one of these categories and do not have to get a sailing or departure permit, you must be able to support your claim for exemption with proper identification or give the authority for the exemption:

1. You are a representative of a foreign government who holds a diplomatic passport; a member of the representative’s household; a servant who accompanies the representative; an employee of an international organization or foreign government whose pay for official services is exempt from U.S. taxes and who has no other U.S. source income; or a member of the employee’s household who was not paid by U.S. sources. However, if you signed a waiver of nonimmigrants’ privileges as a condition of holding both your job and your status as an immigrant, this exception does not apply, and you must get a certificate.
2. You are a student, industrial trainee, or exchange visitor, or the spouse or child of such an individual. To qualify for this exception, you must have an F-1, F-2, H-3, H-4, J-1, J-2 or Q-1, visa. Additionally, you must not have received any income from sources in the U.S. other than:
   • Allowances covering expenses incident to your study or training in the U.S. (including expenses for travel, maintenance, and tuition),
   • The value of any services or accommodations furnished incident to such study or training,
   • Income from employment authorized under U.S. immigration laws, or
   • Interest on deposits, but only if that interest is not effectively connected with a U.S. trade or business.
3. You are a student, or the spouse or child of a student, with an M-1 or M-2 visa. To qualify, you must not have received any income from sources in the U.S. other than:
   • Income from employment authorized under U.S. immigration laws or
   • Interest on deposits, but only if that interest is not effectively connected with a U.S. trade or business.
4. Any of the following applies:
   • You are on a pleasure trip and have a B-2 visa.
   • You are on a business trip, have a B-1 visa or a combined B-1/B-2 visa, or are present in the U.S. under Visa Waiver, and do not stay in the U.S. or any of its possessions for more than 90 days during the tax year.
   • You are passing through the U.S. or any of its possessions, including travel on a C-1 visa or under a contract, such as a bond agreement, between a transportation line and the U.S. Attorney General.
   • You are admitted on a border-crossing identification card.
   • You do not need to carry passports, visas, or border-crossing identification cards because you are (a) visiting for pleasure or (b) visiting for business and do not stay in the U.S. or any of its possessions for more than 90 days during the tax year.
   • You are a resident of Canada or Mexico who commutes frequently to the U.S. to work and your wages are subject to income tax withholding.
   • You are a military trainee admitted for instruction under the Department of Defense and you will leave the U.S. on official military travel orders. However, exception 4 does not apply if the Area Director believes you had taxable income during the tax year, up through your departure date, or during the preceding tax year and that your leaving the U.S. would hinder collecting the tax.