Without a doubt, this summer has brought with it an unrelenting stream of huge movie releases for the theater-going masses to enjoy. In fact, with one full month still left in the season, audiences have poured a record $3.74 billion of their summer spending money into the big screen, easily exceeding last summer's old high mark by nearly $400 million so far.

As we enter August, and with the sunny season close to halfway through, it's time to check out the biggest box-office hits -- and the companies behind them -- in the summer of 2013 to date.

RankTitleCompany / Distributor

Worldwide Gross

Domestic Gross
Production Budget
Domestic Opening Date

Iron Man 3

Disney (NYSE:DIS) / Buena Vista  $866.6  $407.4  $200  5/3/13*
2 Fast & Furious 6 Comcast (NASDAQ:CMCSA) / Universal Studios  $741.2  $237.7  $160  5/24/13
3 Despicable Me 2 Comcast / Universal Studios  $668.5  $314.0   $76  7/3/13
4 Man of Steel Time Warner (NYSE:TWX.DL) / Warner Brothers  $644.2  $287.1  $225


5 Monsters University Disney / Buena Vista  $578.4  $256.8  $200**  6/21/13
6 World War Z Viacom (NASDAQ:VIAB) / Paramount   $474.2  $193.8  $190  6/21/13
7 Star Trek Into Darkness Viacom / Paramount  $450.3  $225.7  $190  5/16/13 
8 The Hangover Part III  Time Warner / Warner Brothers  $350.9  $112.1  $103  5/23/13
9 The Great Gatsby (2013)  Time Warner / Warner Brothers  $330.5  $144.3  $105  5/10/13
10 Epic News Corp. (NASDAQ:NWS) / 20th Century Fox  $244.7  $106.4  $100  5/24/13

Source: boxofficemojo.com; data shown from May 3, 2013, through July 31, 2013.
*Iron Man launched Internationally on April 24, 2013, domestically on May 3, 2013.
**Estimated (Disney has not disclosed the budget for Monsters University). 

Remember, last weekend I compiled a list of the highest-grossing movies of 2013 year to date, and with an extra week in the bag, these summer-only numbers highlight a few points worth noting.

First, Disney's Iron Man 3 predictably still holds the top spot, and not just because the Marvel film was the earliest movie in the list to launch in the U.S. during the summer season. In fact, to put Iron Man 3's dominance in perspective, its worldwide summer gross doesn't even include the $345.4 million it brought in overseas between April 24 and May 2. 

Next, Comcast's Fast & Furious 6 remains in second place thanks to its incredible showing with audiences abroad, and Despicable Me 2 -- which has the lowest production budget of any film on the list by a wide margin -- blew by Time Warner's Man of Steel over the past week to snag the third-place spot both on the summer and overall 2013 lists to date.

Image source: Official Despicable Me 2 Instagram page

Where it really gets interesting, however, is near the bottom of list, which shows international audiences apparently loved The Hangover Part III as well, with its overseas total making up more than any other movie on the list at 68.1% of sales.

Meanwhile, Epic from News Corp's 20th Century Fox managed to edge out Sony Pictures' After Earth and Warner Brothers' Pacific Rim for 10th, just beating their own global summer grosses of $242.3 million and $227.4 million, respectively.

Coming up next ...
Then again, this list could (and probably will) change as summer draws to a close. So which titles have the biggest chance of mixing things up before then?

Remember, 20th CenturyFox's The Wolverine took in nearly $161 million worldwide in the first six days after its June 26 debut, so it's quite possible the mutant movie could at least slice through Epic for the No. 10 spot in the next week or two.

But the existing top 10 may also face a threat from above in the form of Disney's Planes, a spin-off from Pixar's Cars franchise, which is largely expected take home the No. 1 weekend spot when it hits theaters on Aug. 9.

Disney's Planes. Image source: movies.disney.com.

Then again, that's hardly a guarantee. While Disney Pixar's Cars and Cars 2 did well before, Planes was made by DisneyToon Studios, not Pixar, so we can't automatically assume it'll do well.

What's more, other children's movies, most notably DreamWorks' Turbo, have had a rough time dealing with a children's movie slate that's much more crowded than usual, and so are pinning their hopes on a belated international surge as the third quarter rolls on.

In the end, though, it's safe to say movie studios are largely enjoying their banner summer so far.