To answer that question you have to dissect the various roles that knights played in Western Europe. For the sake of your question I'm assuming you're talking about a knight in the 14th century (i.e. a French chevalier). Knights while being potential players in aristocratic/feudal systems were also a potent military force. While they fought dismounted often enough, they are mostly associated with heavy cavalry. The Byzantines had Kataphraktoi which were extremely armored cavalry that they had fielded for centuries. During the time of the Komnenian restoration (roughly 1080 to 1180) the Byzantines had even employed knights from all over Europe as regulars and mercenaries in their army. It's when you compare them socially that snags come up. For much of the empire's history the answer is no. The Byzantine Empire was far more centralized than the rest of Europe, so nobles instead usually competed for titles and positions by gaining the favor of the emperor. The closest aspect we have is called Pronoia which were special privileges that an emperor gave. Rather than being a land grant, they were usually rights or duties that an individual or a group (like a monastery) was able to collect, so say gaining the right to tax a region or to collect the tolls on an important bridge. These privilages were entirely dependent on the emperor and could be revoked at his/her will. Later, however, during the reign of the Komnenoi and their successors this began to change. Land grants were given to aristocrats to appease them in expecting loyalty and possibly military service. However, even then the Pronoia was expected to return to the emperor once the individual passed (so no inheritance). It isn't until the last imperial dynasty, the Palaiologos, that these grants were inheritable. Even then, these grants weren't necessarily land but could be still be rights and duties. Military service/ financial contributions was expected. I wouldn't call this feudal arrangements though as many of the finer details about these grants are unknown.