The top one doesn’t have a clip, but it does have a hexagonal bushing under the cap which keeps it from rolling off of the table. The name on the pencil is “Vanco”:
I’ve got a few Vanco pencils, but they are all Japanese-made duplex pencils, meaning that they contain two leads inside so that turning the cap one way advances one color lead, and turning it the other way withdraws that one and advances another color. This one isn’t anything like that – in fact, if it weren’t for the name I’d think it was made by Ritepoint.
In fact, there is no connection between this pencil and the Japanese company. I found an advertisement for the Vanco Bridge Scoring Pencil in the June, 1936 edition of Popular Mechanics, providing an address of 210 South 16th Street, Philadelphia:
As for that middle example, I don’t have any idea who made it. There were two of these that came my way in a collection, the second of which was missing a cap. There might have been a clip under that cap which has gone missing:
The third one is a bit easier to figure out. That clip and the rosette molded into the top of the cap are calling cards of the Welsh Manufacturing Company of Providence, Rhode Island: