| Xavier University Computer Science | Ohio |
| Xavier University Mathematics | Ohio |
| Xavier University of Louisiana | Louisiana |
| Xavinci, LLC | |
| Xavor Corporation | California |
| Xaxis, LLC | New York |
| XB Software Ltd | Virginia |
| Xbintech, LLC | |
| xBiologix, Inc. | Oregon |
| XBiotech USA, Inc. | |
| XBLUE Networks, LLC | Kansas |
| XBOSoft Ltd | California |
| XBRL International, Inc. | District of Columbia |
| xByte Technologies | Florida |
| Xcase | New York |
| Xcast Labs | California |
| xCBL | Missouri |
| Xccelero, Inc. | Arkansas |
| XCEL Solutions Corporation | New Jersey |
| Xcelerate Restoration Software | Arizona |
| Xcelerium | |
| XcelHR | Maryland |
| Xcell Biosciences, Inc. | California |
| XCell Science | California |
| XCellAssay | California |
| XCellCure, LLC | Missouri |
| Xcellent Technology Solutions | Virginia |
| Xcelligen, Inc. | |
| Xcellimark Digital Agency | Florida |
| Xcellon Biologics | |
| Xcelnet Sytems, Inc. | |
| XcelPros.com | Illinois |
| XCENA, Inc. | |
| XCENT | Pennsylvania |
| Xcentech Computers, LLC | Arizona |
| Xcential Corporation | California |
| Xchange Software | New Jersey |
| XchangeWorx | New York |
| XChat | California |
| Xcimer Energy, Inc. | Colorado |
| Xcision Medical Systems, LLC | Maryland |
| Xcitium | New Jersey |
| xClosure | Utah |
| XComP | Texas |
| XConn Technologies Holdings, Inc. | |
| Xcovery | Florida |
| xCraft UAV | |
| xCubicle | New York |
| xCures | California |
| Xdata Corporation | Colorado |