Chapter 89:3
A Base for a Mukteh Item
3. It is permissible on Shabbos to move a garment that has coins in its pocket, because only the pocket and not the entire garment is considered a base [for the money], and the pocket is considered subordinate ("batel") to the garment (1).
It is, however, forbidden to wear the garment on Shabbos, lest one inadvertantly go out into the public domain while wearing it. (The laws applying to a person on a journey who is carrying money are related in Chapter 68, Law 12.)
[A different ruling applies to money that is placed intentionally] in a drawer of a table (2). It is forbidden to move the table, because the drawer is considered an article in its own right and not an auxiliary of the table (3).
FOOTNOTES:
(1) This halacha is referring to an independent pocket, which consists of a small bag that has been sewn into the garment, and is thus not considered part of the garment (most pockets in men's pants and coats are of this type). Therefore, the money is not considered to be resting on the garment itself, and hence, the garment is not treated as a base. Nevertheless, it is preferable to shake the money out first, before moving the garment.
Different laws apply if the money was in a pocket sewn into the garment along its three sides. If the money was left there with the intent for it to remain there the entire Shabbos (the criteria for creating a base), the garment is considered a base for the money, and may not be moved on Shabbos, even if the money was shaken out. If, however, the money was left there unintentionally, the garment may be moved if the money is shaken off (See Mishna Berura 310:29 and 30).
The bottom-line issue here is whether the money in the pocket is viewed as resting on the garment itself, in which case the garment can become a base, or whether the money is viewed as resting in something which is not a part of the garment, and yet is subordinate to it, because it is attached.
(2) This halacha is dealing with a drawer that can be completely removed from the table. However, a drawer that cannot be completely removed is considered only a subordinate part of the table, and thus, money resting in it, cannot turn the table into a base.
(3) This applies only if the drawer is used exclusively for muktzeh items. Also, as we saw in the previous halacha, if there is something more "important" than the muktzeh item, resting on the table during twilight, then the table may be moved (See Mishna Berura 310:31).