Many half-free slaves were forced to continue to work for the Dutch West India Company even after they were set free, and the company even required half-free blacks to pay a yearly tax consisting of crops that they had raised on their farms.
Source: wiktionary
“Half-free” meant that the slaves themselves were now free, but their children would return to slavery. The Dutch gave a half-free slave named Gratia d'Angola a 10acre farm in the 1640s, centered around what is today one block of Greene Street between Prince Street and Houston Street, in the SoHo neighborhood of Manhattan.
Source: wiktionary
Yet first, the anonymous rabbis and students begin the sequence of explorations in legality of marriage between half-free people by using more general rules of betrothal.
Source: wiktionary