Creature exchange and summoning sickness

[(nameless one)]

Alright, here's a couple of scenarios that needs some clearing:

1) I have a Tarmogoyf on the field with summoning sickness. On my opponent's turn, he decided to cast Gilded Drake. The Drake resolves and it's ability resolves. Now my opponent has the Goyf. Does the same Goyf still has summoning sickness?

2) After the events above, my opponent passes the turn to me. On my turn, I decided to cast a Sower of Temptation and it resolves. The Sower's ability also resolves and I target Goyf with it's ability. After all this fiasco, does the Goyf still have summoning sickness?

3) Following the events on number 1 and 2, if my opponent somehow gave the Goyf haste for only until the end of his turn (by activating Need for Speed), if I steal it back on my main phase, would it still have summoning sickness or would the haste until the end of turn get rid of it's summoning sickness altogether (assuming he never attacked with it for some reason)?

4) So theoretically, if there was a creature with the text: "at the beginning of each player's upkeep, that player gains control of this creature", would that creature always have summoning sickness?

[Whippoorwill]

Yes in both cases.

Unless it starts the turn under your control or gains haste, it will be sick.

[Justin]

From the official comprehensive rules:

302.6. A creature’s activated ability with the tap symbol or the untap symbol in its activation cost can’t
be activated unless the creature has been under its controller’s control continuously since his or her
most recent turn began. A creature can’t attack unless it has been under its controller’s control
continuously since his or her most recent turn began. This rule is informally called the “summoning
sickness” rule.

[Whippoorwill]

3) Following the events on number 1 and 2, if my opponent somehow gave the Goyf haste for only until the end of his turn (by activating Need for Speed), if I steal it back on my main phase, would it still have summoning sickness or would the haste until the end of turn get rid of it's summoning sickness altogether (assuming he never attacked with it for some reason)?

4) So theoretically, if there was a creature with the text: "at the beginning of each player's upkeep, that player gains control of this creature", would that creature always have summoning sickness?

3. It will still be sick since it didn't have haste when you took control of it.

4. Yes, unless it was given haste. It has to start the turn under your control to not be sick.

[(nameless one)]

3. It will still be sick since it didn't have haste when you took control of it.

4. Yes, unless it was given haste. It has to start the turn under your control to not be sick.

Oh okay, thank you very much.