[MrWorkrate]

In case anyone wants a set document regarding MLB's actual stand on these rules, see below. I got this from the Toronto Blue Jays. It's a bit confusing, but that's what the FAQ is for. This should also clear up some of the issues.

PLAYER LIMITS: 40 until opening day, when the number must be reduced to 25 until September 1, when it again becomes 40.

TYPES OF WAIVERS

• OUTRIGHT WAIVERS (OR) — this type of irrevocable waiver needs to be secured in order to Outright a player. An outright is to assign a player to a club’s minor league affiliate without the right of recall. In other words, to remove a player from the 40-man roster. Also a player who has exhausted his options must clear this type of waiver if the club wishes to assign him to minor league affiliate. An outright waiver secured is good for entire waiver period. These waivers are needed from the 31st day of the season through August 31.
• SPECIAL WAIVERS (SPL) — also irrevocable, the special waiver is used for the same purpose as an outright waiver. One difference is these waivers are
used from September 1 to the 30th day of the following season. A secured special waiver is good for seven days, as opposed to being good for an entire period like the outright waiver.
• UNCONDITIONAL RELEASE WAIVER (UR) — this irrevocable waiver is used for the purpose of an unconditional release of a player. At the time of the
request the player shall be removed from all player limits. A player may be informed of the clubs intention to release him on a weekend, but the actual waiver process won’t begin until the following business day. During the time a player is on an unexpired waiver request bulletin he may discuss employment with other clubs but may not contract with another club. If the player has been claimed, he must be informed the end of the two-day period that his contract has been claimed. The player has five days from the time he was
notified of the claim to either accept the assignment or terminate his contract. If the player terminates his contract he forfeits termination pay. Termination pay may vary depending on the time of year.
• MAJOR LEAGUE WAIVER (ML) — this type of revocable waiver is common and it is used to either option a player to a club’s minor league affiliate or assign a player outright to another Major league club from August 1st to the end of the regular season. A player claimed on this type of waiver may be pulled back by the requesting club. This is known as a waiver withdrawal.
Generally a club needs to secure this type of waiver in order to option a player if the date of the assignment is three or more years after the date the
player first reported to a Major League club during a championship season. One year shall be deducted from the above three-year period for each season in which the player may have been charged with an option prior to first reporting to a Major League club during a championship season. A claimed player pulled back by the requesting club may not be assigned and cannot be placed on waivers again (except for UR waivers) for 30 days. When ML waivers are asked for a second time in the same period the request shall state that it is irrevocable.

ASSIGNMENT OF PLAYER CONTRACTS:
• Ten and Five Rule: Players with ten or more years of Major League service (MLS), the last five of which have been with one Club, shall not be assignable to another Major League Club without the Player’s written consent.
• When a player with five or more years of MLS is asked by his club to consent to an assignment to the National Association, he has three choices;
1. Accept the assignment, 2. Refuse the assignment, 3. Elect Free Agency
• Any player who has at least three years of MLS and whose contract is assigned outright to a National Association club may elect, in lieu of accepting such assignment, to become a free agent.
• Any player whose contract is assigned outright to a National Association club for second time or any subsequent time in his career may elect, in lieu of
accepting such assignment, to become a free agent. Unlike a player with five or more years of MLS, this type of player does not have the option of refusing the assignment.

OPTIONAL ASSIGNMENT: to assign a player from the active 25-man roster to a minor league affiliate with the right of recall. The player remains on the 40-man roster.

RECALL: to add a player from your reserve limit (40-man roster) to the 25-man roster. This player must serve at least 10 days on option in order to be recalled unless he is replacing a player placed on the disabled list.

OUTRIGHT ASSIGNEMENT:
• MAJOR TO MINOR: to assign a player to the Club’s minor league affiliate without the right of recall. The player is removed from the 40-man roster.
• MAJOR TO MAJOR: to assign a player from one Club’s 40-man roster to another Club’s 40-man roster. This transaction is more commonly known as a trade.

DESIGNATED FOR ASSIGNMENT:
• When a club that has reached it 40 and /or 25 man roster limit, either reinstates a player, or acquires a new player (through a selection, a signing, a trade or a waiver claim); they must designate a player for assignment or release. If they are going to assign the player, they must do it within 10 days.

WAIVER WITHDRAWALS:
• Waiver request may only be withdrawn on players who have been claimed on a Major League Waiver wire. If a player is claimed on a Major League Waiver wire, the request must be withdrawn within two business days or the contract will be awarded to the eligible club. During the two-day waiver withdrawal period the requesting Club can try to negotiate a deal with the eligible Club and make a waiver claim award under the terms of that deal.