On October 17, 2000, President Clinton signed into law the "American Competitiveness in the 21st Century Act of 2000." The new law increased the H-1B "training fund fee" from $500 to $1000, increased the maximum number of new H-1B visas to 195,000 per year through 2003, and allows persons previously issued a visa or otherwise provided H-1B status to begin working for a new H-1B employer as soon as the new employer files a "nonfrivolous" H-1B petition for the alien. This last concept is known as a "portable H-1B alien."
In order to be classified as a "portable H-1B alien"
A "portable H-1B alien" who travels internationally while the new petition is pending with the INS can be readmitted to the US in H-1B status if the following conditions are met:
IMPORTANT EXCEPTION. If the original H-1B petition has expired the alien is not allowed to reenter the United States in H-1B status until the new H-1B petition is approved. This is the case even if he was previously considered a "portable H-1B alien."