2006 United States broadcast television realignment

In January 2006, the United States' two "second-tier" television networks, UPN and The WB, announced they would both cease operations on September 15 and 17 respectively, and their operations would be transferred to a new joint-venture "fifth" network, The CW. Meanwhile, Fox Television Stations (which owned several UPN and WB-affiliated stations in large cities that were blocked from affiliating with The CW) signed up with MyNetworkTV, a new "sixth" network owned by then-parent company News Corporation's Fox Entertainment Group.

Background
In January 1995, The WB Television Network and the United Paramount Network (UPN) were launched, each hoping to recreate the success of the Fox network, which had launched in October 1986 and became one of America's "major" networks through the successes of several early series (such as The Simpsons, Married... with Children, The X-Files, Melrose Place, Martin, In Living Color, COPS, Beverly Hills, 90210, and Fox Kids' airings of the Mighty Morphin Power Rangers) and its 1993 deal with the National Football League (NFL) to assume the broadcast rights to the National Football Conference (NFC) from CBS. Like with Fox at the time, The WB targeted a mostly teenage and young adult audience; UPN, however, aimed its programming at a broader demographic of adults between 18 and 49 years of age.

All three networks had been joint ventures between major Hollywood studios and large owners of previously independent stations – The WB was owned by the Warner Bros. Entertainment division of Time Warner, in a joint venture with the Tribune Company, and UPN was founded by Chris-Craft Industries, in a programming partnership with Paramount Pictures. In October 1993, Chris-Craft and the Paramount Stations Group reached affiliation agreements with most of the independents owned by the respective groups to serve as charter UPN affiliates. That November, Tribune cut affiliation deals with The WB for all eight independents it owned at the time (including stations in New York City, Los Angeles and Chicago) – as well as a station in Boston that Tribune bought from the Gannett Company the following year, though only seven would join the network at launch due to the company's Atlanta station affiliating with CBS (its New Orleans station would follow suit in 1996, switching its affiliation to ABC); Chris-Craft and Paramount also each owned independents in large and mid-sized markets (with the former owning stations in New York City and Los Angeles).

Both new networks launched to limited fanfare and generally poor results. Over the course of 11½ seasons, despite a number of minor-hit or cult-hit series such as Star Trek: Voyager, Star Trek: Enterprise, Charmed, 7th Heaven, Gilmore Girls, Girlfriends, Buffy the Vampire Slayer, Felicity, Moesha, Dawson's Creek, The Parkers, One on One, Roswell, and Kids' WB's airing of the anime Pokémon, neither network was able to attain the stature that Fox had gained in its first decade, much less that of the longstanding "Big Three" television networks (ABC, CBS and NBC). By early 2006, both networks were losing money, although The WB had been profitable a few seasons earlier; in slight contrast, UPN had never turned a profit and had already lost $800 million in its first five years of operation. Reports indicated that the prospects for both networks were fading quickly.

A further complication was the various shifts in network and affiliate ownership at UPN. Shortly before its launch, Paramount Pictures' corporate parent Paramount Communications was purchased by Viacom, which later purchased a 50 percent stake in UPN in December 1996, and acquired CBS in 2000. Viacom was permitted to keep interests in both networks, in effect, resulting in the Federal Communications Commission (FCC) lifting its long-standing ban on television station duopolies. Chris-Craft's relations with Viacom were strained in February 2000 when the latter firm exercised a contractual right to force Chris-Craft to either buy Viacom out of UPN, or sell its stake in the network to Viacom within a 45-day grace period. Chris-Craft subsequently filed a lawsuit against Viacom in the New York Supreme Court to block the CBS merger on grounds that a pact reached between Chris-Craft and Viacom in 1997 disallowed either company from owning "any interest, financial or otherwise" in "any competing network" through January 2001; however, New York Supreme Court judge Herman Cahn ruled against Chris-Craft's move for a permanent injunction motion in March 2000. Chris-Craft could not find a suitable partner and sold its interest in UPN to Viacom for $5 million that April. This had the adverse effect of making UPN one of the few networks not to have owned-and-operated flagship stations in New York City and Los Angeles.

Similarly, The WB had the distinction of being the only American broadcast network never to have had an O&O, as although minority owner Tribune operated its core charter stations, Time Warner held majority ownership in the network (with a maximum interest of 77.5 percent, during the final years of The WB's existence). Time Warner did acquire Atlanta independent WTBS (which served as the originating feed of then-superstation TBS) through its 1996 merger with the Turner Broadcasting System; however, WATL (which Tribune would acquire in 1999) served as the WB affiliate for that market throughout the network's run.

That August, when Chris-Craft put its television stations – most of them UPN affiliates – up for sale, it sold them to News Corporation's Fox Television Stations subsidiary instead of Viacom. At the time, Fox seemed to be a willing partner in UPN, but made no firm commitment. On September 24, 2003, Fox Television Stations renewed affiliation agreements for its nine UPN stations for three years through 2006. On December 31, 2005, Viacom split into two companies: a new company keeping the Viacom name (which took the original company's film and most of its cable television properties), and CBS Corporation (essentially the old Viacom renamed, which retained the broadcast properties, along with Showtime Networks). In this "split", ownership of UPN went to CBS Corporation.

The new "fifth" and "sixth" networks
On January 24, 2006, CBS Corporation and Time Warner announced they would shut down both UPN and The WB that fall. In place of these two networks, a new "fifth" network that would be jointly owned by both companies, would launch, with a lineup made primarily of the most popular programs from both The WB and UPN. The network was given the name "The CW Television Network" ("CW" representing the first letters in "CBS" and "Warner Bros.").

The CW immediately announced ten-year affiliation agreements with 16 WB affiliates owned by Tribune Broadcasting, and 11 UPN owned-and-operated stations under CBS ownership, giving the new network coverage in all of the top 13 markets and a reach of 48 percent of the country. The remaining affiliates were to be drawn from the pool of stations affiliated with UPN and The WB. The CW took on The WB's base scheduling model (two hours of prime time programming each Monday through Friday and five hours on Sundays, a two-hour daytime block on weekdays and a five-hour Saturday morning children's block), which was larger in scope compared to UPN, which aired prime time programming only on weekdays and a two-hour repeat block on weekends at the time of the CW announcement.

It was immediately clear that most media markets which had stations that were owned by Tribune would receive the CW affiliation, leaving Fox Television Stations, UPN's second largest affiliate group (after the UPN O&Os owned by CBS Television Stations), without any network programming during primetime hours. Rumors began to circulate that Fox would develop its own network for those affected stations and others left out in the merger. The rumors proved true, and on February 22, 2006, Fox announced the launch of its own network, MyNetworkTV, a programming service meant to fill the two nightly primetime hours that would open up on its UPN and WB-affiliated stations after the start of The CW. Fox also offered the service to other stations.

Stations
Following the CW network announcement, the new network immediately announced ten-year affiliation agreements with the Tribune Company and CBS Television Stations. Tribune committed 16 stations – including its flagship broadcast stations WGN-TV in Chicago; KTLA in Los Angeles; and WPIX in New York City – that were previously affiliated with The WB, while CBS committed 11 of its UPN stations – including WPSG in Philadelphia; KBCW in San Francisco; and WUPA in Atlanta. These stations combined to reach 48 percent of the United States. Both groups also owned several UPN- and WB-affiliated stations that did not join The CW in overlapping markets. As part of its agreement, Tribune agreed to divest its 22.5 percent ownership interest in The WB – a decision that the company made in part to avoid shouldering shutdown costs for the network – and did not acquire an interest in The CW.

The CW and MyNetworkTV would eventually reach 95 percent of all television households in the United States. In markets where both UPN and WB affiliates operated, only one station became a CW affiliate or a MyNetworkTV affiliate. CW executives were on record as preferring the "strongest" stations viewership-wise among The WB and UPN's existing affiliates. However, as the reorganization was structured not as a merger in the legal sense, but as a new network launching concurrent with the shutdowns of The WB and UPN, The CW was not obligated by existing affiliations with The WB and UPN. It had to negotiate affiliation agreements from scratch with individual stations.

As a result, in some markets, the new CW affiliate or MyNetworkTV affiliate was a different station from either the former WB and UPN stations. In Helena, Montana, Ion Television affiliate KMTF became a CW station. In Las Vegas, Nevada, independent KFBT chose to affiliate with The CW. In Honolulu, Hawaii, The CW did not become available in the market until early December 2006, where it was carried on a digital subchannel of local Fox affiliate KHON-TV. The network also affiliated with some digital channels, mainly newly launched subchannels of a local Big Four affiliate, in several markets.

Under the new network, a new service called The CW Plus  began serving Nielsen markets with rankings of 100 and lower, featuring a pre-supplied master schedule of programs acquired from the syndication market in addition to CW network programming. The CW Plus is structured similarly to The WB 100+ Station Group, which supplied locally branded WB-affiliated cable channels. In most cases, distribution for The CW Plus covers not only cable but broadcast television as well, including the digital subchannels discussed above.

On March 1, 2006, five stations – four WB affiliates and one UPN affiliate – were the first outside the core CBS and Tribune stations to sign affiliation deals with The CW. By May 18, 2006, 174 stations had signed agreements to become affiliates of The CW and MyNetworkTV, reaching 105 million households and covering 95.3 percent of the country (the latter two figures excluding stations in Puerto Rico and the U.S. Virgin Islands).

Station groups that signed up a large number of their stations as CW affiliates included Pappas Telecasting Companies, ACME Communications and Sinclair Broadcast Group, although many other large groups, including Hearst-Argyle Television, Clear Channel Communications and Belo Corporation had signed up selected stations. Sinclair signed deals to carry the networks in early May, despite reservations with The CW and MyNetworkTV reporting demands for reverse compensation.

While WGN-TV in Chicago became a charter affiliate of The CW, its former national counterpart WGN America never aired programs from The CW through a formal affiliation when it operated as WGN-TV's out-of-market superstation feed prior to December 2014 (although it did carry reruns of select CW series in marathon form in 2013), as the network has sufficient enough affiliate coverage that The CW did not need to use the national WGN feed to carry its programming; WGN America had previously carried WB programming from that network's January 1995 launch until October 1999, when Tribune Broadcasting and Time Warner mutually decided that The WB's national broadcast coverage had increased to a level that allowed the WGN national feed to discontinue carrying the network.

Several affiliates changed their call letters to reflect their new CW and MyNetworkTV affiliations; e.g., KPWB-TV in Des Moines became KCWI, WNPA-TV in Pittsburgh became WPCW, WJWB in Jacksonville became WCWJ, WHCP in Portsmouth, Ohio became WQCW, WEWB in Albany, New York became WCWN, KWCV in Wichita, Kansas became KSCW, WBDC in Washington, D.C. became WDCW, KBHK in San Francisco became KBCW, KHWB in Houston became KHCW. Some stations retained call signs that referred to UPN and The WB, such as WUPA in Atlanta and KWBA-TV in Tucson, Arizona, respectively. Between February and August 2006, News Corporation's MyNetworkTV stations and CBS Corporation's CW stations dropped all references to UPN and The WB from their branding.

Due to the availability of "instant duopoly" digital subchannels, and the overall lack of a need to settle for a secondary affiliation with shows aired in problematic timeslots, both The CW and MyNetworkTV launched with far greater national coverage than that enjoyed by UPN and The WB when they started in 1995. For several years, UPN had coverage gaps in the top 30 markets, and by 2005 had only managed to reach 86 percent of the population. This resulted in secondary affiliations with other networks (with some dual WB-UPN affiliates airing the latter network's programming immediately after The WB's primetime lineup, and vice versa) and diluted ratings when programs were shown out of their intended timeslots, or the lack of the program airing at all (a problem experienced by many Star Trek fans with Star Trek: Voyager and Star Trek: Enterprise).

Comparisons to 1994 realignment
The WB and UPN were the first major television networks to shut down since the collapse of the DuMont Television Network in 1956, although other small broadcast television networks have also ceased operations over the years. Given the merger of the two networks to create The CW (as well as the eventual launch of MyNetworkTV and the proliferation of digital subchannels), the scope of the realignment caused the largest single shakeup in American broadcast television since the Fox/New World Communications alliance of 1994, which preceded the subsequent launches of UPN and The WB the following year that drastically reduced the number of independent television stations in the U.S., some of which had been marketed and distributed as superstations as recently as the mid-1990s.

While The CW's debut affected more markets, unlike the Fox/New World deal of the mid-1990s, it was unlikely to cause the same degree of viewer confusion as almost no affiliates of the four major networks dropped those affiliations to become CW affiliates. Only two former Big Four affiliates switched their primary affiliation, in both cases from Fox to MyNetworkTV:
 * In the Jackson, Mississippi, market, Fox affiliate WUFX swapped affiliations with WDBD in the summer before joining MyNetworkTV the following season after three seasons with Fox. Unrelated UPN affiliate WRBJ, which signed on the air in early 2006, joined The CW.
 * In the Fort Smith-Fayetteville, Arkansas, market, low-power Fox affiliate KPBI-CA switched to MyNetworkTV, along with KPBI. Fox had moved its affiliation to full-power KFTA-TV, formerly a satellite of NBC affiliate KNWA-TV. None of the three stations that were available (the two KPBI's and UPN affiliate KFDF-CA) joined The CW; they were all owned by Equity Broadcasting, which shunned The CW in every one of its markets (KFDF-CA joined the Equity-owned Retro Television Network instead). The CW would finally come to the market the following year on a cable-only channel available via Cox Communications (and eventually on digital subchannels of the market's ABC affiliate, KHBS/KHOG-TV). Equity would eventually declare bankruptcy in 2009 due to a number of factors involving the digital transition and problems with RTV which led it to losing control of that network to Luken Communications.

There were several other cases where Big Four affiliates picked up The CW, MyNetworkTV, or both as a secondary affiliation on their main channel or as a digital subchannel affiliation, even in markets where viable non-network affiliate stations remained.

Network affiliation repercussions
In media markets where there were separate affiliates of The WB and UPN, one local station was left out in the merger. Many of these stations signed with MyNetworkTV including the vast majority of the Fox stations acquired in the 2001 acquisition of BHC Communications (the former Chris-Craft stations). Additionally, MyNetworkTV signed with three Tribune stations that did not take the CW affiliation: WPHL in Philadelphia, WATL in Atlanta and KTWB in Seattle. Tribune had indicated interest in Fox-developed programming blocks such as MyNetworkTV for stations that did not pick up the CW affiliation; the company announced on May 15 that the aforementioned stations would join MyNetworkTV. In contrast, CBS initially seemed more hostile to MyNetworkTV, and announced its remaining UPN affiliates – KTXA in the Dallas/Fort Worth metroplex, WSBK-TV in Boston, WBFS-TV in Miami/Fort Lauderdale, and WUPL in New Orleans as well as WB affiliate WTCN-CA in West Palm Beach – would all become independents. Four of the five stations, excluding KTXA, eventually all joined MyNetworkTV.

Some stations bypassed by The CW that did not take MyNetworkTV instead opted to become (or revert to) independents. For example, the two remaining former Viacom-owned UPN stations – WSBK and KTXA – reverted to their roots as independents (the latter was constrained to independence in any event due to Fox-owned KDFI, affiliating with MyNetworkTV). As a consequence, in three of the top 10 media markets – Boston, Dallas/Fort Worth and San Francisco – programs from The WB, UPN and MyNetworkTV were all available to viewers from September 5 to 17. MyNetworkTV affiliated with longtime former independents WZMY in Derry, New Hampshire (serving the Boston market) and KDFI, while in San Francisco the network affiliated with KRON-TV; WB affiliate KBWB reverted to independent status. Other stations elected to become (or revert to) independents as well, particularly in situations where either more than two non-major network affiliate stations existed or another station picked up an affiliation with The CW or MyNetworkTV via a digital subchannel.

Additionally, four former UPN affiliates became affiliates of "Big Four" networks themselves: Additionally, while some stations joined newly established or lesser-known broadcast networks such as RTV), whose now-defunct parent company Equity Broadcasting did not commit any of its WB affiliates to The CW, other stations (mainly digital subchannels, cable channels such as those that were WB 100+ cable channels, and struggling low-power stations) which received neither The CW nor the MyNetworkTV affiliation opted instead to cease operations entirely. For example, in Dayton, Ohio, the "UPN17" cable channel run by CBS affiliate WHIO-TV closed down at the end of 2006.
 * WJKT in Jackson, Tennessee, and the digital subchannel of WBOC in Salisbury, Maryland, joined Fox on August 21, 2006.
 * WLQP-LP in Lima, Ohio, became the local ABC affiliate on September 1, 2006.
 * WSWG in Valdosta, Georgia, became a CBS affiliate and added MyNetworkTV as a digital subchannel on September 4.

Many households around the country were not able to see The CW when it launched, because stations in several markets that agreed to carry the station on a digital subchannel were unsuccessful in securing deals with Time Warner Cable to carry these subchannels on basic cable lineups. These markets included Cincinnati, Honolulu, Charleston, South Carolina, El Paso, Corpus Christi, Palm Springs and Lima, Ohio.

In Cincinnati, eventual independent WBQC-LP moved UPN programming on July 4 to the early morning hours, with the intention of promoting the station's "Independence Day" programming in its place. Before the merger, Granite Broadcasting Corporation agreed to sell KBWB and WDWB to AM Media, a unit of private equity firm ACON Investments; as The CW affiliated with KBCW and WKBD, respectively, the Granite-AM Media deal collapsed, prompting Granite to sue CBS and Time Warner over the failed deal. In New Orleans, CBS sued Belo in February 2006, alleging Belo tried to back out of a deal for WUPL after Tribune-owned WNOL was named the market's CW affiliate, but before WUPL's affiliation with MyNetworkTV was announced. The deal, already complicated in the aftermath of Hurricane Katrina, would create a duopoly between Belo's WWL-TV and WUPL.

Closing UPN and The WB
UPN quietly ceased operations on September 15, 2006, by fading to black after its usual airing of WWE Friday Night SmackDown!; however, the Fox-owned lame-duck UPN affiliates dropped the network entirely on August 31 in order for MyNetworkTV to launch on September 5. Because of this, UPN was entirely unavailable for its final two weeks in those markets; as a result, SmackDown was on several Tribune-owned charter CW affiliates, including WPIX, KTLA, and WGN, per an earlier arrangement with the WWE.

The WB closed on September 17 with The Night of Favorites and Farewells, a five-hour block of pilot episodes of the network's past signature series, including Felicity, Angel, Buffy the Vampire Slayer and Dawson's Creek. Commercial breaks shown on the network that evening featured re-airings of past image campaigns and network promotions, promo spots given to cable networks that carried these shows in off-network syndication, as well as ads for each series' TV-on-DVD box set. The final night of WB programming, which aired against NBC Sunday Night Football, netted low ratings.

Post-realignment
After launching, The CW usually finished fifth in the Nielsen ratings and even fell behind Spanish-language network Univision at times. While the network had some successful series such as Gossip Girl, The Vampire Diaries and Arrow, concerns over The CW's future led Tribune to rebrand their CW affiliates in a way that deemphasized its network affiliation. Pappas Telecasting Companies cited The CW's poor performance as a factor in its Chapter 11 bankruptcy filing. In September 2008, The CW outsourced its five-hour Sunday block to Media Rights Capital (MRC); the network dropped its Sunday night lineup in 2009 and would not air on that night until 2018, with only two hours to program.

The CW's ratings struggles eventually subsided in later years: the network beat NBC for the first time in the key 18–49 demographic for a single calendar night on November 21, 2013. Other recent series successes (including the revival of the U.S. version of the improv comedy series Whose Line Is It Anyway?, The Flash and Jane the Virgin) helped The CW increase its ratings year-over-year by the 2014–15 season – at which point, The CW posted its highest season average total viewership since the 2007–08 season with 2.15 million.

MyNetworkTV struggled to gain an audience upon its launch. Due to its consistently low ratings with their initial program lineup of telenovelas and its 2007 retool to include more unscripted programming (including televised martial arts events) and movies, MyNetworkTV became a rerun-focused syndication service in 2009. The service's last first-run program, SmackDown, moved to Syfy and USA Network in October 2010.

Nexstar Media Group, which acquired Tribune Media in 2019 after a prior failed merger attempt with Sinclair Broadcast Group, assumed operations of The CW on August 15, 2022, and acquired a 75-percent ownership stake in The CW on October 3, 2022; former joint owners Paramount Global (successor to CBS Corporation) and Warner Bros. Discovery (successor to Time Warner) retained a 25-percent stake, split at nominal 12.5-percent stakes for both companies. Under the agreement, Paramount was given a right with the transaction to disaffiliate all eight of their CW affiliates, which was exercised on May 5, 2023. By the time of the disaffiliations on September 1, Nexstar repatriated the CW affiliations onto their MyNetworkTV affiliates in Philadelphia, San Francisco and Tampa–St. Petersburg, announced the purchase of Detroit station WADL through affiliate company Mission Broadcasting, and signed long-term affiliation agreements with Hearst Television, Gray Television, Sinclair Broadcast Group, and the E.W. Scripps Company.