Malphite doesn't own ANYONE top.

Riven won't even poke you, but placing Malphite top is like placing a passive creep farmer top; He won't die, but he won't kill either. He will just basically organize a farmfest for both parties for 20 minutes long.

The only time when you should place Malphite top is when your jungler has enough burst. I don't even see how Malphite has any chance to beat Riven top 1v1. Malphite is just a creep farming bot top, 'nuff said.

tryndamere?
i dont think so... if riven is bad then yea
but 1st rule when laning against tryn is not to let him get any rage without losing lots of hp
so an agressive riven will give tryn a hard time
tryn will eventually be pushed to his turret though getting him the opportunity to hit some creeps and depending on the jungler and riven positioning she might get in danger
but by himself tryn will have a hard time

id say mao though i really prefer him jungle
except for him malph should do fine
jax will be a risky counter as the one that gets the adavantage in gold will likely win the trades jax's dodge is barely as usefull against an ad caster as against an as reliant champ

T
E
E
M
O

He always gets ignored, but his blinds makes all bruisers cry.
Sure, you can argue that Riven has her combo abilities and does not need her auto attack.
But if you think that you should reread her passive and try again.

I never see Fiora lose vs a Riven, but it should be true.

Fioras passive + her insane burst along with shield should out trade riven with no problem, Riven will be forced to build armor against her otherwise she will fall like bricks.

I'd say Fiora counters Riven from my own Experience, Wingsofdeathx played her vs Dyrus Riven, and Oddone had to babysit him all day so Fiora wouldn't wreck him. They tried tower diving her and she ulted and got a double lol :P

Riven is overrated imo, Lategame Fiora is practically a joke with that ulti...works like Karthus ult does in teamfights, dishing out 500+scaling dmg to 3 and even more to the target (4ppl)

teemo does make me cry a bit.....but i beat most teemo's caus they push their lane really hard. I can keep my cs up pretty well and they expose themselves to ganks.
As a riven you cannot trade with teemo caus of the **** blind but you can cs and kill him with jungleassistance

yorick denies your statement.

and i think that's a viable option, considering a team's strategy (go noc?)