From this google patent,
http://www.google.com/patents?id=E7ShAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=false
Patents do not proof if it exists. It's simply a possibility google has thought of.
However there is also the fact that fast link building already has some algorithms with a throttle back incorporated.
For instance this one: http://googlepublicpolicy.blogspot.com/2009/01/detecting-new-googlebombs.html
Patent + throttle back algo already in place + loads of people across boards reporting the "sandbox" phenomena, i would say there's a high probability that the sandbox does exist.
Sadly nothing is fact when guessing.
Cheers
First of all, I am not guessing. You didn't read my original post, apparently. I'm going by what I've seen from various client sites and my own after running bulk backlinks day after day after day after day after day.
Second of all, the patent does not discuss sandboxing, it discusses lower scoring of a page when the links come in too fast, i.e. high velocity. Part of my service is that the links get indexed over time, although many times people DO experience a sandbox for a brief period of time, and I've already discussed it here, it's called a "dance". Their sites come back because new links get indexed and change things. Plus, some of my clients like to blast the pages I create for them to give them a push. That has made my network pretty strong.
But this thread isn't about my network, it's about the sandbox effect. And my whole point is that it's not the number of links that pushes your site down. It's other factors, and the patent you posted proves my point.
There is a sandbox. I've seen my competitor's website get sandbox, I've seen my sites get sandboxed. Complete deindex from google. It never happens with yahoo or bing though. But definitely google sandboxes sites. There were many sites from experiments and tests in blackhatworld that proves there is a sandbox.
Getting deindexed is not sandboxed, it's being banned.
Honestly, the people saying there is no sandbox are coming from people that are selling backlinks, scrapebox blasts, and xrumer blasts.
I don't want to offend anyone but I have to say the truth. You guys have no idea about seo. Sell your backlink blasts or whatever. Leave the climbing of serps and falling of serps to people who actually know what they are doing and talking about.
I fully admitted that I sell backlinks, that wasn't the point of my thread. I'm not trying to trick anybody into buying from me here, I'm trying to help people realize that they need to step up their SEO game instead of running around with these myths in their head. And by "step-up" I mean
do the tests yourself. Don't take my word for it, please. Do the tests and you'll see that I'm right.
One more thing, just for my own pride here

, I most certainly do know quite a bit about SEO, I wouldn't have hundreds of my sites ranking and pulling in cash if I didn't. My link-building service used to be a big part of my life, and now it's just a fraction of my income. How would that happen if didn't know what I'm talking about? About 75% of my income comes from SEO traffic. I'd say I must be doing something right...
For anyone else who is looking for some genuine help here, this is what I have to offer: if you buy a bulk backlinking service and get your site sandboxed, there's probably one of the following going on:
1. keyword stuffing on your site
2. too high link velocity
3. no high quality backlinks
4. duplicate content (a la Panda update)
Over n out..