I am getting tired of these calls day after day.....every day,sometimes 2-3 times.
So much for the don't call me

Just started calling yesterday.  Have not answered.  No messages left.

Area code is San Francisco, CA.

Got a call here in Canada from 4156212343 - no message - no idea who it was.

Hi there,

If you are a victim of these calls, please contact your local authorities/phone company. If the caller asks for any personal information, that's fraud and only *you* can press charges as the victim of the fraud.

I picked a contact email from Crowdflower's website. john@crowdflower.com.

I got a reply from John Le (john@doloreslabs.com) at Crowdflower and he wrote " have no idea why this is happening or who is using our number.  It looks like someone is using our number to call lots of people.  We're trying to figure out why.  Sorry for the annoyance."

The bottom of the email is the footer "c: 301-461-1760 | o: 415.621.2343 | 455 Valencia Street, San Francisco, CA 94103 | CrowdFlower"

I called the number and it is indeed Crowdflower's automative phone system.

I have never really answered the call when this number shows up. Maybe I should to see who's on the other line.

Can the local authorities really do something about it?

Maybe i'll email EVERYONE at Crowdflower and complain! hahhaa....

Thanks for posting the info cmelchor.  These people keep calling me 2-3 times a day as well, and it just started this month.  One time last week it seems they accidentally left me message... but all I heard was people talking (very muffled) in the background for a few seconds.

This number has been calling me for the past two weeks almost everyday or a few times a day.  I've answered a few times and have received no reply on the other end, or they just hang up.  Don't know what's going on but it's QUITE annoying!

ive gotten calls from this number too!! A few times a day.  I answered once but noone on the other end.  It finally stopped before New Year's!!

I contacted CrowdFlower by email and they claimed that " Someone managed to hack the system and is using CrowdFlower's number as their caller ID."

About an hour later I received another call (the 6th one) from 415-621-2343.  They claimed to be from MBNA, but I was suspicious, although very good it felt like the caller may have been phishing for personal information -- asked for my email address (which I did not give) and asked for a secret password, suggesting that many people use their place of birth as password -- that seemed VERY suspicious to me.  I refused to give any information.

I googled 415-621-2343 and found this company called Crowd Flower http://crowdflower.com

I found some contact names here: http://crowdflower.com/images/marketing/SIGIRpaper.pdf

I picked a contact email john@crowdflower.com and told him to stop harrassing people!! WTF!!?

I got a reply from John Le (john@doloreslabs.com) at Crowdflower and he wrote "I have no idea why this is happening or who is using our number.  It looks like someone is using our number to call lots of people.  We're trying to figure out why.  Sorry for the annoyance."

The bottom of the email is the footer "c: 301-461-1760 | o: 415.621.2343 | 455 Valencia Street, San Francisco, CA 94103 | CrowdFlower"

I called the number and it is indeed Crowd flower's automative phone system.

I have never really answered the call when this number shows up. Maybe I should to see who's on the other line.

Can the local authorities really do something about it?

Maybe i'll email EVERYONE at Crowdflower and complain! hahhaa....
I think EVERYONE that is getting a call from this number should bombard them with emails and complain!!!

Call my cell phone several times a day. Do not leave a message. Pick up and no one is there. Ready to throw my cell phone out the window.

I have received a number of calls from 415-621-2343 (both during the day at least twice and at night), they never leave a message and they hang up if answered.

They call 3 to 4 times per day & last night it was at 9pm!  I finally picked it up just now & they hung up on me.

The past few days i've been getting that number calling me too. 2 or 3 times a day. i found this.... http://crowdflower.com/images/marketing/SIGIRpaper.pdf

i emailed them and told them to stop harrassing people!! WTF!!?