The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
Estimated average burden
hours per response: 23.8
COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
8point3 Energy Partners LP CL A RPT LTDPT 282539105 1 49 SH   DFND N/A 49 0 0
ABB Ltd SPONSORED ADR 000375204 1 49 SH   DFND N/A 49 0 0
Acuity Brands, Inc. COM 00508Y102 3 15 SH   DFND N/A 15 0 0
Adient PLC ORD SHS G0084W101 0 6 SH   DFND N/A 6 0 0
Advanced Energy Industries, Inc. COM 007973100 1 22 SH   DFND N/A 22 0 0
Algonquin Power & Utilities COM 015857105 1 114 SH   DFND N/A 114 0 0
American Water Works Company, Inc. COM 030420103 11 119 SH   DFND N/A 119 0 0
Anadarko Petroleum Corp COM 032511107 7,220 134,598 SH   DFND N/A 134,598 0 0
Andeavor COM 03349M105 3,341 29,221 SH   DFND N/A 29,221 0 0
Andeavor Logistics LP COM UNIT LP INT 03350F106 581,861 12,597,120 SH   DFND N/A 11,090,938 0 1,506,182
Antero Midstream GP LP COM SHS REPSTG 03675Y103 112,038 5,681,443 SH   DFND N/A 5,108,503 0 572,940
Antero Midstream Partners LP UNT LTD PARTN 03673L103 301,436 10,380,013 SH   DFND N/A 8,871,201 0 1,508,812
Antero Resources Corp COM 03674X106 6,898 363,067 SH   DFND N/A 363,067 0 0
Apache Corp COM 037411105 2 42 SH   DFND N/A 42 0 0
Andarko Petroleum Corporation UNIT 99/99/9999 032511404 24,023 693,100 SH   DFND N/A 693,100 0 0
Aqua America, Inc. COM 03836W103 1 31 SH   DFND N/A 31 0 0
Aquaventure Holdings Ltd SHS G0443N107 4 228 SH   DFND N/A 228 0 0
Atlantica Yield PLC SHS G0751N103 39 1,833 SH   DFND N/A 1,833 0 0
Autoliv Inc COM 052800109 1 8 SH   DFND N/A 8 0 0
Autoweb Inc COM 05335B100 1 163 SH   DFND N/A 163 0 0
Badger Meter, Inc. COM 056525108 3 53 SH   DFND N/A 53 0 0
Baker Hughes, a GE Company, LLC CL A 05722G100 2 69 SH   DFND N/A 69 0 0
BorgWarner Inc COM 099724106 1 24 SH   DFND N/A 24 0 0
BP Midstream Partners LP UNIT LTD PTNR 0556EL109 145,723 7,084,272 SH   DFND N/A 6,273,901 0 810,371
BP PLC-Spons ADR SPONSORED ADR 055622104 2,148 51,096 SH   DFND N/A 51,096 0 0
Brookfield Renewable Energy Partner PARTNERSHIP UNIT G16258108 20 564 SH   DFND N/A 564 0 0
Buckeye Partners, L.P. UNIT LTD PARTN 118230101 535,728 10,811,865 SH   DFND N/A 9,656,313 0 1,155,552
C&J Energy Services Inc COM 12674R100 1 19 SH   DFND N/A 19 0 0
Cabot Oil & Gas Corp. COM 127097103 20,132 703,908 SH   DFND N/A 703,908 0 0
Carrizo Oil & Gas Inc COM 144577103 4,977 233,880 SH   DFND N/A 233,880 0 0
Celanese Corporation COM SER A 150870103 2 16 SH   DFND N/A 16 0 0
Centennial Resource Development, In CL A 15136A102 20,359 1,028,200 SH   DFND N/A 1,028,200 0 0
Chart Industries, Inc. COM PAR $0.01 16115Q308 0 7 SH   DFND N/A 7 0 0
Cheniere Energy Inc. COM NEW 16411R208 324,777 6,032,262 SH   DFND N/A 5,855,175 0 177,087
Cheniere Energy Partners LP COM UNIT 16411Q101 1 36 SH   DFND N/A 36 0 0
Chevron Corp COM 166764100 2 18 SH   DFND N/A 18 0 0
Cimarex Energy Co COM 171798101 12,519 102,609 SH   DFND N/A 102,609 0 0
Cms Energy Corp COM 125896100 148 3,138 SH   DFND N/A 3,138 0 0
Concho Resources Inc COM 20605P101 19,540 130,074 SH   DFND N/A 130,074 0 0
Connecticut Water Service, Inc. COM 207797101 1 16 SH   DFND N/A 16 0 0
ConocoPhillips COM 20825c104 2 28 SH   DFND N/A 28 0 0
Continental Resources Inc COM 212015101 14,131 266,775 SH   DFND N/A 266,775 0 0
Core Laboratories N.V. COM N22717107 1 10 SH   DFND N/A 10 0 0
Covanta Holding Corporation COM 22282E102 22 1,300 SH   DFND N/A 1,300 0 0
Cypress Semiconductor Corporation COM 232806109 1 33 SH   DFND N/A 33 0 0
Danaher Corporation COM 235851102 5 54 SH   DFND N/A 54 0 0
DCP Midstream LP COM UT LTD PTN 23311P100 125,989 3,467,911 SH   DFND N/A 3,467,911 0 0
Devon Energy Corporation COM 25179M103 12,241 295,668 SH   DFND N/A 295,668 0 0
Diamondback Energy Inc COM 25278X109 18,566 147,056 SH   DFND N/A 147,056 0 0
Dominion Energy Inc. COM 25746U109 205 2,534 SH   DFND N/A 2,534 0 0
Dominion Energy Midstream Partners COM UT REP LTD 257454108 171,292 5,625,338 SH   DFND N/A 4,897,304 0 728,034
Dril-Quip, Inc. COM 262037104 1 20 SH   DFND N/A 20 0 0
DTE Energy Company COM 233331107 4 40 SH   DFND N/A 40 0 0
DTE Energy Company UNIT 99/99/9999 233331883 2,137 39,600 SH   DFND N/A 39,600 0 0
Duke Energy Corporation COM NEW 26441C204 3 32 SH   DFND N/A 32 0 0
Eastman Chemical Co COM 277432100 2 17 SH   DFND N/A 17 0 0
Ecolab Inc. COM 278865100 4 32 SH   DFND N/A 32 0 0
Edison International COM 281020107 2 36 SH   DFND N/A 36 0 0
Enbridge Energy Management, LLC SHS UNITS LLI 29250X103 26,780 1,999,974 SH   DFND N/A 1,999,974 0 0
Enbridge Energy Partners, L.P. COM 29250R106 140,227 10,154,054 SH   DFND N/A 10,154,054 0 0
Enbridge Inc COM 29250N105 195,624 5,001,897 SH   DFND N/A 5,001,897 0 0
Energy Recovery Inc COM 29270J100 1 72 SH   DFND N/A 72 0 0
Energy Transfer Equity, L.P. COM UT LTD PTN 29273V100 524,224 30,372,176 SH   DFND N/A 25,416,145 0 4,956,031
Energy Transfer Partners, L.P. UNIT LTD PRT INT 29278N103 707,138 39,460,844 SH   DFND N/A 36,195,856 0 3,264,988
Enlink Midstream Partners, LP COM UNIT REP LTD 29336U107 127,248 8,278,989 SH   DFND N/A 8,278,989 0 0
Enlink Midstream, LLC COM UNIT REP LTD 29336T100 73,474 4,174,680 SH   DFND N/A 4,174,680 0 0
Ensco PLC SHS CLASS A G3157S106 0 35 SH   DFND N/A 35 0 0
Enterprise Products Partners L.P. COM 293792107 1,099,272 41,466,322 SH   DFND N/A 35,985,573 0 5,480,749
EOG Resources Inc COM 26875P101 27,282 252,826 SH   DFND N/A 252,826 0 0
EQT Corp COM 26884L109 14,034 246,559 SH   DFND N/A 246,559 0 0
EQT GP Holdings LP COM UNIT REP 26885J103 44,862 1,667,725 SH   DFND N/A 1,385,400 0 282,325
EQT Midstream Partners, LP UNIT LTD PARTN 26885B100 564,174 7,717,832 SH   DFND N/A 6,635,923 0 1,081,909
Esco Technologies Inc. COM 296315104 2 35 SH   DFND N/A 35 0 0
Extraction Oil & Gas, LLC COM 30227M105 4,973 347,496 SH   DFND N/A 347,496 0 0
Exxon Mobil Corp COM 30231G102 3 35 SH   DFND N/A 35 0 0
Fairmount Santrol Holdings Inc. COM 30555Q108 2,443 467,045 SH   DFND N/A 467,045 0 0
FireEye Inc COM 31816Q101 1 70 SH   DFND N/A 70 0 0
First Solar Inc COM 336433107 1 19 SH   DFND N/A 19 0 0
First Trust North American Energy I NO EMER ENERGY 33738D101 1,030 41,926 SH   DFND N/A 41,926 0 0
Forum Energy Technologies, Inc. COM 34984V100 1 41 SH   DFND N/A 41 0 0
Genesis Energy L.P. UNIT LTD PARTN 371927104 111,057 4,969,012 SH   DFND N/A 4,473,695 0 495,317
Gentex Corporation COM 371901109 1 24 SH   DFND N/A 24 0 0
Gulfport Energy Corp COM NEW 402635304 1 53 SH   DFND N/A 53 0 0
Halcon Resources Corp COM PAR NEW 40537Q605 7,343 970,000 SH   DFND N/A 970,000 0 0
Halliburton Company COM 406216101 2,652 54,263 SH   DFND N/A 54,263 0 0
Hannon Armstrong Sustainable Infras COM 41068X100 44 1,842 SH   DFND N/A 1,842 0 0
Helmerich & Payne, Inc. COM 423452101 1 20 SH   DFND N/A 20 0 0
Hess Corp COM 42809H107 1 13 SH   DFND N/A 13 0 0
Holly Energy Partners, L.P. COM UT LTD PTN 435763107 109,924 3,383,317 SH   DFND N/A 3,383,317 0 0
HollyFrontier Corporation COM 436106108 1,796 35,071 SH   DFND N/A 35,071 0 0
Hortonworks Inc COM 440894103 1 50 SH   DFND N/A 50 0 0
IDEX Corporation COM 45167R104 4 29 SH   DFND N/A 29 0 0
InfraREIT Inc. COM 45685L100 20 1,080 SH   DFND N/A 1,080 0 0
Knot Offshore Partners LP COM UNITS Y48125101 10,167 416,667 SH   DFND N/A 416,667 0 0
Itron, Inc. COM 465741106 6 81 SH   DFND N/A 81 0 0
JPMorgan Alerian MLP Index ALERIAN ML ETN 46625H365 3,669 133,565 SH   DFND N/A 37,261 0 96,304
Keane Group Inc. COM 48669A108 2,034 106,974 SH   DFND N/A 106,974 0 0
Kinder Morgan Inc COM 49456B101 282,578 15,637,988 SH   DFND N/A 15,637,988 0 0
Laredo Petroleum, Inc. COM 516806106 4,212 396,976 SH   DFND N/A 396,976 0 0
Lear Corporation COM NEW 521865204 1 3 SH   DFND N/A 3 0 0
Lindsay Corporation COM 535555106 1 6 SH   DFND N/A 6 0 0
Magellan Midstream Partners, L.P. COM UNIT RP LP 559080106 997,023 14,054,460 SH   DFND N/A 12,171,944 0 1,882,516
Magna International Inc COM 559222401 2 44 SH   DFND N/A 44 0 0
Marathon Oil Corp COM 565849106 2 115 SH   DFND N/A 115 0 0
Marathon Petroleum Corp COM 56585A102 2,448 37,099 SH   DFND N/A 37,099 0 0
Micron Technology Inc COM 595112103 0 12 SH   DFND N/A 12 0 0
MiX Telematics Ltd SPONSORED ADR 60688N102 26 2,000 SH   DFND N/A 2,000 0 0
Monolithic Power Systems Inc COM 609839105 3 27 SH   DFND N/A 27 0 0
MPLX LP COM UNIT REP LTD 55336V100 859,654 24,236,080 SH   DFND N/A 21,139,565 0 3,096,515
MRC Global Inc. COM 55345K103 0 27 SH   DFND N/A 27 0 0
Mueller Water Products, Inc. COM SER A 624758108 5 409 SH   DFND N/A 409 0 0
National Fuel Gas Co NJ COM 636180101 37,244 678,266 SH   DFND N/A 678,266 0 0
NATIONAL OILWELL VARCO INC COM 637071101 1 22 SH   DFND N/A 22 0 0
NCS Multistage Holdings Inc COM 628877102 0 21 SH   DFND N/A 21 0 0
Newfield Exploration Co COM 651290108 8,364 265,258 SH   DFND N/A 265,258 0 0
Newpark Resources, Inc. COM PAR $.01NEW 651718504 1 91 SH   DFND N/A 91 0 0
Nextera Energy Inc COM 65339F101 358 2,295 SH   DFND N/A 2,295 0 0
Nextera Energy Partners LP COM UNIT PART IN 65341B106 2,458 57,012 SH   DFND N/A 57,012 0 0
Nisource Inc COM 65473P105 35,413 1,379,545 SH   DFND N/A 1,379,545 0 0
Noble Energy Inc COM 655044105 1,329 45,600 SH   DFND N/A 45,600 0 0
Noble Midstream Partners LP COM UNIT REPST 65506L105 123,574 2,471,465 SH   DFND N/A 2,238,398 0 233,067
NRG Energy Inc. COM NEW 629377508 1 24 SH   DFND N/A 24 0 0
NRG Yield, Inc. CL C 62942X405 5 251 SH   DFND N/A 251 0 0
NuStar Energy L.P. UNIT COM 67058H102 73,607 2,457,650 SH   DFND N/A 2,457,650 0 0
NVIDIA Corporation COM 67066G104 4 19 SH   DFND N/A 19 0 0
Occidental Petroleum Corp COM 674599105 2 24 SH   DFND N/A 24 0 0
Oceaneering International Inc. COM 675232102 1 27 SH   DFND N/A 27 0 0
Olin Corporation COM PAR $1 680665205 1 42 SH   DFND N/A 42 0 0
ONEOK, Inc COM 682680103 828,706 15,504,315 SH   DFND N/A 13,966,888 0 1,537,427
Ormat Technologies, Inc. COM 686688102 2 30 SH   DFND N/A 30 0 0
Parsley Energy, Inc. CL A 701877102 8,419 285,968 SH   DFND N/A 285,968 0 0
Pattern Energy Group Inc. CL A 70338P100 33 1,559 SH   DFND N/A 1,559 0 0
Patterson-UTI Energy, Inc. COM 703481101 1,416 61,550 SH   DFND N/A 61,550 0 0
PDC Energy Inc COM 69327R101 3,753 72,826 SH   DFND N/A 72,826 0 0
Pembina Pipeline Corp COM 706327103 178,927 4,942,024 SH   DFND N/A 4,942,024 0 0
Pentair plc SHS G7S00T104 8 111 SH   DFND N/A 111 0 0
Phillips 66 COM 718546104 1,108 10,953 SH   DFND N/A 10,953 0 0
Phillips 66 Partners LP COM UNIT REP INT 718549207 532,595 10,160,228 SH   DFND N/A 9,003,164 0 1,157,064
Pinnacle West Capital Corporation COM 723484101 1 12 SH   DFND N/A 12 0 0
Pioneer Natural Resources Co COM 723787107 28,160 162,917 SH   DFND N/A 162,917 0 0
Plains All American Pipeline, L.P. UNIT LTD PARTN 726503105 592,529 28,707,797 SH   DFND N/A 24,815,591 0 3,892,206
Plains GP Holdings, L.P. LTD PARTNR INT A 72651A207 180,594 8,227,530 SH   DFND N/A 8,227,530 0 0
PPL Corporation COM 69351T106 3 93 SH   DFND N/A 93 0 0
QEP Resources Inc. COM 74733V100 1 68 SH   DFND N/A 68 0 0
Range Resources Corp COM 75281A109 9,290 544,560 SH   DFND N/A 544,560 0 0
Rice Midstream Partners LP UNIT LTD PARTN 762819100 132,665 6,179,074 SH   DFND N/A 6,179,074 0 0
Royal Dutch Shell PLC SPONS ADR A 780259206 7,638 114,500 SH   DFND N/A 114,500 0 0
RPC, Inc. COM 749660106 1 48 SH   DFND N/A 48 0 0
RSP Permian, Inc. COM 74978Q105 13,434 330,242 SH   DFND N/A 330,242 0 0
Schlumberger, Ltd. COM 806857108 4 66 SH   DFND N/A 66 0 0
Semgroup Corp CL A 81663A105 93,652 3,101,044 SH   DFND N/A 3,101,044 0 0
Sempra Energy COM 816851109 154 1,437 SH   DFND N/A 1,437 0 0
Shell Midstream Partners LP UNIT LTD INT 822634101 588,079 19,720,962 SH   DFND N/A 17,388,484 0 2,332,478
SM Energy Co COM 78454L100 3,335 151,059 SH   DFND N/A 151,059 0 0
Spectra Energy Partners, LP COM 84756N109 243,282 6,152,805 SH   DFND N/A 5,379,275 0 773,530
Splunk Inc COM 848637104 1 12 SH   DFND N/A 12 0 0
Sunrun Inc COM 86771W105 2 294 SH   DFND N/A 294 0 0
Superior Energy Services, Inc. COM 868157108 1 74 SH   DFND N/A 74 0 0
Symantec Corp COM 871503108 2 70 SH   DFND N/A 70 0 0
Tallgrass Energy GP, LP SHS CL A 874696107 88,726 3,446,992 SH   DFND N/A 3,144,833 0 302,159
Tallgrass Energy Partners, LP COM UNIT 874697105 345,779 7,541,529 SH   DFND N/A 6,697,896 0 843,633
Targa Resources Corp. COM 87612G101 353,335 7,297,291 SH   DFND N/A 6,659,051 0 638,240
TC Pipeline, L.P. UT COM LTD PRT 87233Q108 1 16 SH   DFND N/A 16 0 0
TechnipFMC PLC COM G87110105 1 31 SH   DFND N/A 31 0 0
Terraform Power Inc COM CL A 88104R209 21 1,754 SH   DFND N/A 1,754 0 0
Tesla Inc. COM 88160R101 12 39 SH   DFND N/A 39 0 0
Tetra Tech, Inc. COM 88162G103 2 51 SH   DFND N/A 51 0 0
The Goodyear Tire & Rubber Company COM 382550101 1 31 SH   DFND N/A 31 0 0
Tortoise North American Pipeline Fu TORTOISE NRAM PI 56167N720 2,974 127,299 SH   DFND N/A 127,299 0 0
Transcanada Corp COM 89353D107 289,946 5,961,052 SH   DFND N/A 5,961,052 0 0
U.S. Silica Holdings, Inc. COM 90346E103 6,999 214,970 SH   DFND N/A 214,970 0 0
USA Compression Partners LP COMUNIT LTDPAR 90290N109 1 33 SH   DFND N/A 33 0 0
Valero Energy Corp COM 91913Y100 2 26 SH   DFND N/A 26 0 0
Valero Energy Partners LP COM UNT REP LP 91914J102 252,505 5,674,274 SH   DFND N/A 4,878,476 0 795,798
Verisk Analytics Inc COM 92345Y106 0 5 SH   DFND N/A 5 0 0
Watts Water Technologies, Inc. CL A 942749102 3 37 SH   DFND N/A 37 0 0
WEC Energy Group, Inc. COM 92939U106 222 3,335 SH   DFND N/A 3,335 0 0
Western Gas Equity Partners, LP COMUNT LTD PT 95825R103 44,138 1,187,796 SH   DFND N/A 993,456 0 194,340
Western Gas Partners LP COM UNIT LP IN 958254104 664,770 13,823,458 SH   DFND N/A 12,170,202 0 1,653,256
Westlake Chem Corp COM 960413102 3,676 34,505 SH   DFND N/A 34,505 0 0
Westlake Chemical Partners LP COM UNIT RP LP 960417103 2,747 110,115 SH   DFND N/A 110,115 0 0
Whiting Petroleum Corp COM 966387409 0 6 SH   DFND N/A 6 0 0
Williams Companies, Inc COM 969457100 532,311 17,458,554 SH   DFND N/A 15,982,347 0 1,476,207
Williams Partners L.P. COM UNIT LTD PAR 96949L105 504,828 13,017,750 SH   DFND N/A 11,194,177 0 1,823,573
WPX Energy Inc COM 98212B103 9,088 645,893 SH   DFND N/A 645,893 0 0
Xylem Inc. COM 98419M100 11 166 SH   DFND N/A 166 0 0