19. Section 51 of the Principal Act is amended—
(a) by omitting from paragraph (4) (c) “or” (last occurring);
(b) by adding at the end of paragraph (4) (d) “or”;
(c) by adding at the end of subsection (4) the following paragraph:
“(e) the purchaser of the service.”; and
(d) by omitting subsection (5).